Safety Standards for Underground Coal Mine Ventilation

SUMMARY: This proposed rule revises stayed provisions of the Mine

Safety and Health Administration's existing safety standards for

ventilation of underground coal mines. The proposal also revises,

clarifies or reproposes certain other provisions in the rule, includes

some new provisions, and addresses concerns raised during public

informational meetings and later discussions.

DATES: Written comments must be submitted on or before July 18, 1994.

Commenters are encouraged to send comments on a computer disk along

with their original comments in hard copy.

ADDRESSES: Send written comments and computer disks to the Mine Safety

and Health Administration, Office of Standards, Regulations and

Variances, room 631, Ballston Tower No. 3, 4015 Wilson Boulevard,

Arlington, Virginia 22203.

FOR FURTHER INFORMATION CONTACT: Patricia W. Silvey, Director, Office

of Standards, Regulations and Variances, MSHA, phone (703) 235-1910.

SUPPLEMENTARY INFORMATION:

I. Paperwork Reduction Act

This proposal contains information collection requirements in

Secs. 75.312, 75.342, 75.360, 75.363, 75.364 and 75.382. These

paperwork requirements have been submitted to the Office of Management

and Budget (OMB) for review under section 3504(h) of the Paperwork

Reduction Act of 1980. The respondents would be mine operators. The

burden hour estimate for Sec. 75.312 includes the time to record any

fan monitoring system malfunctions, electrical or mechanical

deficiencies in the monitoring system and any sudden increase or loss

in mine ventilating pressure, the time for recording main mine fan

defects that are corrected and for the mine foreman and mine

superintendent to countersign the record. The burden hour estimate for

Sec. 75.342 includes the time to develop a written maintenance program,

to record the calibration tests and to file the record. The burden hour

estimate for Sec. 75.360 includes the expanded examination time and the

time for the mine superintendent to countersign the records. The burden

hour estimates for Sec. 75.362 includes the expanded examination time.

The burden hour estimate for Sec. 75.363 includes the time for

recording the hazard, the corrective action taken, the certified person

initialing the record, the mine foreman and mine superintendent

countersigning the record and for filing the record. The burden hour

estimate for Sec. 75.364 includes the time for the mine superintendent

to countersign the records. The burden hour estimate for Sec. 75.382

includes the time for recording the results of the examination, for the

mine foreman and the mine superintendent to countersign the record, and

for filing the record. The information collected would be used by MSHA

to assess compliance with the proposed requirements. The information

collection requirements contained in the proposal are discussed below.

Proposed Sec. 75.312(g)(1) would require that the records of all

defects found during the daily fan examination be made by the end of

the shift on which the examination is made. The record would be made in

a state-approved book or in a bound book with sequential machine-

numbered pages.

Proposed paragraph (g)(2)(i) would require that the certified

copies of data produced by the fan monitoring systems be maintained

separate from other computer generated reports or data.

Proposed paragraph (g)(2)(ii) would require that a record be made

of any fan monitoring system malfunction, electrical or mechanical

deficiency in the monitoring system and any sudden increase or loss in

mine ventilating pressure. The record would be made by the end of the

shift on which the review of the data is completed and would be made in

a state-approved book or in a bound book with sequential machine-

numbered pages.

Proposed paragraph (g)(3) would require that at mines permitted to

shut down main mine fans under Sec. 75.311, if a pressure recording

device is not used, a record be made of the time and fan pressure

immediately before the fan is stopped, and after the fan is restarted

and the fan pressure stabilizes. The record would be made in a state-

approved book or in a bound book with sequential machine-numbered

pages.

Proposed paragraph (g)(4) would require that a record of the

results of the tests be made by the end of the shift on which the

monthly test of the automatic fan signal device or the automatic

closing doors is completed. Persons making these tests would record the

results of the tests in a state-approved book or in a bound book with

sequential machine-numbered pages.

Proposed paragraph (g)(5) would require that the records required

under paragraphs (g)(1) through (g)(4) be countersigned by the mine

foreman, and the mine superintendent, mine manager, or other mine

official to whom the mine foreman is directly accountable.

MSHA estimates that it would take about 4 minutes for the mine

foreman and mine superintendent to countersign the records and would

take an additional 5 minutes to record main mine fan defects corrected

and an additional 10 minutes to record any fan monitoring system

malfunctions, electrical or mechanical deficiencies in the monitoring

system and any sudden increase or loss in mine ventilating pressure.

The total estimated recordkeeping burden for all affected mines would

be 29,608 hours of which large mines would incur 9,657 hours and small

mines would incur 19,951 hours.

Proposed paragraph Sec. 75.342(a)(4)(ii) would require mine

operators to develop and adopt a written maintenance program that would

have to be made available for inspection by authorized representatives

of the Secretary and the representative of miners. MSHA estimates that

it would take about 1 hour to develop a written maintenance program.

Proposed paragraph (a)(4)(iii) would require that a record of all

calibration tests of methane monitors be made in a state-approved book

or in a bound book with sequential machine-numbered pages.

Proposed paragraph (a)(4)(iv) would require the record of the

calibration tests to be kept for one year from the date of the test and

to be retained at a surface location at the mine and made available for

inspection by authorized representatives of the Secretary and the

representative of miners.

A record of calibration tests would be required to be made monthly

at all mines. MSHA estimates that it would take about 5 minutes to

complete a record. The total estimated recordkeeping burden for all

affected mines that concerns developing a written maintenance program

and maintaining a record of tests would be 2,910 hours of which large

mines would incur 1,464 hours and small mines would incur 1,446 hours.

Proposed Sec. 75.360(b)(3) would require a preshift examination to

be made for sections capable of producing coal by energizing equipment

on the section. MSHA estimates that this would affect some mines and

take up to an additional hour per examination.

Proposed paragraph (f) would require that a record of the results

of each preshift examination, including a record of hazardous

conditions and their locations found by the examiner during each

examination and of the results and locations of air and methane

measurements, be made in a book provided for that purpose on the

surface.

The record would be made by either the certified person who made

the examination or by a person designated by the operator. If the

record is made by someone other than the examiner, the examiner would

be required to verify the record by initials and date. A record would

also be made by a certified person of the action taken to correct

hazardous conditions found during the preshift examination. The records

would be countersigned by the mine foreman, and by the mine

superintendent, mine manager, or other mine official to whom the mine

foreman is directly accountable. The record would be made in a state-

approved book or in a bound book with sequential machine-numbered

pages. MSHA estimates that it would take about 2 minutes for the mine

superintendent to countersign the records.

The total estimated recordkeeping burden and the extended

examination time for all affected mines would be 60,987 hours of which

large mines would incur 56,015 hours and small mines would incur 4,972

hours.

Proposed Sec. 75.362(a)(1) would expand the on-shift examination to

include sections where anyone is assigned to work during the shift,

such as those sections where maintenance work is performed. In

addition, proposed paragraph (a)(2) would add a new requirement for on-

shift examinations to be conducted to assure compliance with the

respirable dust control parameters specified in mine ventilation plans.

MSHA estimates that these provisions will expand on-shift examinations

by up to 45 minutes. MSHA estimates that the total burden hours related

to expanding the on-shift examination would be 111,434, of which small

mines would incur 18,007 hours and large mines would incur 93,427

hours.

Proposed Sec. 75.363 would require that any hazardous conditions

discovered be posted, corrected immediately, and recorded. Proposed

paragraph (a) would require a conspicuous danger sign to be posted at

any area where hazardous conditions are found. The hazardous condition

would have to be corrected immediately and only persons designated by

the operator to correct or evaluate the condition would be allowed to

enter a posted area.

Proposed paragraph (b) would require that a record including a

description and location of the hazardous condition and the corrective

action taken be kept in a book maintained on the surface at the mine.

The record would be made by the completion of the shift on which the

hazardous condition is found. This record would not be required for

shifts when no hazardous conditions are found or for hazardous

conditions found during the preshift or weekly examinations because

these examinations have separate recordkeeping requirements.

Proposed paragraph (c) would require that the record be made by

either the certified person or by a person designated by the operator.

If the record is made by a person designated by the operator, the

certified person would be required to verify the record by initials and

date by or at the end of the shift for which the examination was made.

The record would be countersigned by the mine foreman and by the mine

superintendent, mine manager, or other mine official to whom the mine

foreman is directly accountable. The record would be made in a state-

approved book or in a bound book with sequential machine-numbered

pages.

Proposed paragraph (d) would require that the record be retained at

a surface location at the mine for at least one year and be made

available for inspection by authorized representatives of the Secretary

and the representative of miners.

Under the existing rule, the recordkeeping requirement for on-shift

examinations was included in paragraph (g) of Sec. 75.362 and the

requirement for retention was in paragraph (h). Under the proposal,

paragraphs (g) and (h) are removed from Sec. 75.362 and transferred to

paragraphs (c) and (d) of Sec. 75.363. As the requirement would remain

the same, there would be no change in the paperwork burden associated

with the recordkeeping for on-shift examinations. However, this

recordkeeping requirement would be new for hazardous conditions found

during supplemental examinations and at times when an on-shift

examination would not be required. This recordkeeping requirement would

also be new for hazardous conditions found during the examination

following a main mine fan stoppage of 15 minutes or longer (75.313).

MSHA estimates that a record of hazardous conditions found during

supplemental examinations would be made about 24 times a year at each

large mine and about 4 times a year at each small mine. MSHA further

estimates that it would take about 5 minutes to complete a record and

an additional 7 minutes for the certified person to initial and the

mine foreman and mine superintendent to countersign the record. The

total estimated recordkeeping burden for all affected mines would be

4,092 hours, of which large mines would incur 3,514 hours and small

mines would incur 578 hours.

In addition, MSHA estimates that a record of hazardous conditions

found during an examination following a main mine fan stoppage of 15

minutes or longer would be made about 100 times a year at large mines

and 100 times a year at small mines. MSHA further estimates that it

would take about 5 minutes to complete a record and an additional 4

minutes for the mine foreman and mine superintendent to countersign the

record. The total estimated recordkeeping burden for all affected mines

would be 28 hours, of which large mines would incur 14 hours and small

mines would incur 14 hours.

Proposed Sec. 75.364(b) would require an examination for hazardous

conditions and for noncompliance with mandatory safety or health

standards that could result in a hazardous condition to be made weekly

by a certified person.

Proposed paragraph (h) would require that at the completion of any

shift during which a portion of a weekly examination is conducted a

record be made of the results of each weekly examination, including a

record of hazardous conditions, their locations found by the examiner

during each examination, the corrective action taken, and the results

and location of air and methane measurements. The record would be made

by the person making the examination or a person designated by the

operator. If made by a person other than the examiner, the examiner

would be required to verify the record by initials and date. The record

would be countersigned by the mine foreman and by the mine

superintendent, mine manager, or other mine official to whom the mine

foreman is directly accountable. The record would be made in a state-

approved book or in a bound book with sequential machine-numbered

pages.

MSHA estimates that it would take about 2 minutes for the mine

superintendent to countersign the record and an additional 3 minutes to

record noncompliance with mandatory safety or health standards that

could result in a hazardous condition. The total estimated

recordkeeping burden for all affected mines would be 5,457 hours, of

which large mines would incur 3,048 hours and small mines would incur

2,409 hours.

Existing Sec. 75.382(c) requires mechanical escape facilities,

including automatic elevators, to be examined weekly.

Proposed paragraph (h) would require that a record of the results

of the examination of mechanical escape facilities, including any

deficiency found and the corrective action taken, be made at the

completion of any shift during which the weekly examination is made.

The record would be made by the person making the examination. The

record would be countersigned by the mine foreman and by the mine

superintendent, mine manager, or other mine official to whom the mine

foreman is directly accountable. The record would be made in a state-

approved book or in a bound book with sequential machine-numbered

pages.

Proposed paragraph (i) would require that the records be retained

for at least one year at a surface location at the mine and made

available for inspection by authorized representatives of the Secretary

and representative of miners.

A record of examinations would be required to be made weekly at all

mines that would be governed by Sec. 75.382. MSHA estimates that it

would take about 5 minutes to complete a record and an additional 4

minutes for the mine foreman and mine superintendent to countersign the

record. The total estimated recordkeeping burden for all affected mines

would be 3,360 hours, of which large mines would incur 3,300 hours and

small mines would incur 60 hours.

Send comments regarding these burden estimates or any other aspect

of this collection of information, including suggestions for reducing

these burdens, to Patricia W. Silvey, Director, Office of Standards,

Regulations and Variances, MSHA, room 631, Ballston Tower #3, 4015

Wilson Boulevard, Arlington, Virginia 22203, and directly to the Office

of Information and Regulatory Affairs, Office of Management and Budget,

Attention: Steve Semenuk, Desk Officer for MSHA, room 3001, New

Executive Office Building, Washington DC 20503.

New Technology for Recordkeeping

As the complexity of mining increases with the introduction of

technological improvements and innovations, MSHA foresees that

electronic storage of records in computer systems could enhance health

and safety by facilitating rapid access to critical information by

individuals with the authority and responsibility to direct or redirect

resources to correct potentially unsafe or unhealthy conditions.

Records electronically stored also could facilitate trend analysis,

allowing for earlier detection and correction of potential hazards. In

addition, the efficiency of accessing various records at a desktop

computer workstation could promote a more integrated and effective

approach to mine safety and health.

MSHA is considering allowing electronic storage of the records and

certifications required by this proposed rule. Although the Agency

envisions that such storage would most likely be on a personal computer

at the mine site, central storage of the records would not be precluded

as long as immediate access to those records at the mine site were

available. The use of electronic media for storage of such records

would have to be accessible, secure, verifiable, and provide for

necessary backups. MSHA would require both the availability of

immediate screen viewing of the information and the availability of a

hard copy printout within 1 hour of a request by MSHA or an authorized

representative of miners. The records would have to be kept in a secure

manner that would preclude alteration once the required information is

correctly entered. MSHA would have to be able to verify that the

electronic signature of the persons required to sign or countersign

such records is authentic and entered in a timely manner. Finally, the

records would have to be periodically backed-up on media separate from

the computer so that computer failure would not result in the loss of

data. Although MSHA has not specifically included any such provisions

in this proposal, the Agency requests comments on the storage of

records on electronic media, in particular on the safeguards necessary

to ensure the integrity of such storage.

II. Background

The Mine Safety and Health Administration (MSHA) is proposing to

revise the definition of return air in Sec. 75.301, and would revise

Secs. 75.310(a)(3), (a)(4) and (c), 75.311(d), 75.312(a), (b)(1), (c),

(d), (g)(1), (g)(3), (g)(4) and (h), 75.313(c)(2), (c)(3), (d)(1)(i),

(d)(1)(ii) and (d)(2), 75.321(a), 75.323(b)(1)(ii), (c)(1), and

(d)(2)(i), 75,333(a), (b)(1), (b)(3), (b)(4) and (e)(1), 75.334(e),

75.340(a), 75.342(a)(4), 75.344(a)(1), 75.360(a), introductory text to

(b), (b)(1), (b)(3), (b)(4), (b)(6), introductory text to (c), (c)(1),

introductory text to (c)(3) and (f), 75.362(a)(1), (c)(1), (d)(1)(iii),

and (d)(2), 75.364(a), (b) and (h), 75.370(a)(3), (c)(1), and (f),

75.371(b), (s), (z) and (bb), 75.372(b)(3), 75.380(d)(3), (d)(4)(ii),

(d)(5), (f) and (i)(2) of its existing safety standards for ventilation

of underground coal mines. MSHA is also proposing to redesignate

Sec. 75.312(f) as (f)(1), and paragraphs (g)(2) and (g)(3) as (g)(3)

and (g)(4). Section 75.344(b)(2) would be redesignated as

Sec. 75.344(b)(3). Existing Sec. 75.360(e) would be removed and (f)

through (h) would be redesignated as (e) through (g). Existing

Sec. 75.362(a)(2), (g) and (h) would be removed and (d)(1)(i) and

(d)(1)(ii) would be redesignated as (d)(1)(ii) and (d)(1)(iii).

Existing Sec. 75.370(b)(1) through (f) would be redesignated as (c)(1)

through (g). MSHA is further proposing to add new Secs. 75.312(f)(2),

(g)(2), and (g)(5), 75.320(e), 75.330(c), 75.333(h), 75.344(b)(2) and

(e), 75.360(b)(8) through (b)(10), 75.362(a)(2), (d)(1)(i) and (g),

75.363, 75.370(b), 75.372(b)(19) and (b)(20), 75.380(d)(4)(iii),

75.380(f)(2) and (f)(6) and 75.382(g), (h) and (i). New introductory

text would be added to Sec. 75.388(c), and new introductory text would

be added to Sec. 75.389(c). These revisions are proposed in accordance

with section 101 of the Federal Mine Safety and Health Act of 1977, 30

U.S.C. 811.

On May 15, 1992, MSHA published a notice in the Federal Register

revising its safety standards for ventilation of underground coal mines

(57 FR 20868). To assure that mine operators could effectively plan and

implement necessary changes, MSHA delayed the effective date of the

final rule from August 16, 1992, to November 16, 1992 (57 FR 34683).

Through discussions with the mining community, the Agency became

aware of potential problems that could arise through the implementation

of Secs. 75.344(a)(1) and 75.313. MSHA therefore initially stayed these

two provisions until July 1, 1993, (57 FR 53856) extended the stay

until July 1, 1994 (58 FR 31908), and has extended the stay until the

completion of this rulemaking (59 FR 18485). Sections 75.314, 75.315

and 75.345 are in effect during the duration of the stay. As proposed,

Sec. 75.313 would revise paragraphs (c)(2), (c)(3), (d)(1)(i),

(d)(1)(ii) and (d)(2) of stayed Sec. 75.313 and delete interim

Secs. 75.314 and 75.315. Also as proposed, Sec. 75.344(a)(1) would

revise stayed Sec. 75.344(a)(1) and delete interim Sec. 75.345. Section

75.344(a)(1) was stayed to determine whether requiring all compressors

to be located in a noncombustible structure or area could create a fire

hazard due to overheating.

Section 75.313 was stayed to further consider the effect of fan

stoppages in certain mines. As written, the standard would have allowed

circuits and equipment used to withdraw persons from the mine to remain

energized until the persons are withdrawn. The Agency is concerned that

under some conditions methane could migrate into haulageways after a

fan stoppage. This could result in a hazard if all underground

electrical circuits are not promptly deenergized and all mechanized

equipment is not shut off.

On November 16, 1992, the United States Court of Appeals for the

District of Columbia Circuit (D.C. Circuit) issued an order staying the

application of the air quality standards for oxygen and carbon dioxide

at 30 CFR 75.321(a). MSHA is continuing to litigate this application of

the standard. However, in conformance with the Court's order, the

Agency has suspended indefinitely Sec. 75.321(a) and redesignated the

first sentence of previous Sec. 75.301 to remain in effect as

Sec. 75.321(c) (57 FR 55457, November 25, 1992). The result is that,

with the exception of bleeder systems and worked-out areas, the Agency

is continuing to apply the oxygen and carbon dioxide limits to all

areas where persons work or travel as in previous Sec. 75.301. As

proposed, Sec. 75.321(a) would revise suspended Sec. 75.321(a) and

delete interim Sec. 75.321(c).

III. Discussion of the Proposed Rule

A. General Discussion

Underground coal mine ventilation affects various aspects of the

safety and health of miners. Proper underground coal mine ventilation

is necessary to protect against mine fires and explosions due in part

to the presence of explosive gases, oxygen-deficient atmospheres, and

accumulations of other harmful gases and float coal dust. Ventilation

is also a primary method of controlling miners' exposure to respirable

dust and preventing the development of pneumoconiosis (black lung). In

enacting the statutory ventilation standards of the Mine Act, Congress

expressly recognized these and related dangers associated with

inadequate ventilation:

[V]entilation of a mine is important not only to provide fresh

air to miners, and to control dust accumulation, but also to sweep

away liberated methane before it can reach the range where the gas

could become explosive. In terms then of the safety of miners, the

requirement that a mine be adequately ventilated becomes one of the

more important safety standards under the * * * Act.

S. Rep. No. 181, 95th Cong. 1st Sess. 41 (1977), reprinted in Senate

Subcommittee on Labor, Committee on Human Resources, 95th Cong., 2d

Sess., Legislative History of the Federal Mine Safety and Health Act of

1977, at 629 (1978).

On May 15, 1992, the Agency published a comprehensive revision of

its ventilation standards for underground coal mines. Because of the

scope and extensive coverage of the new standards, the Agency held a

series of informational meetings across the country to brief the mining

public on the provisions of the new rule. As a result of these meetings

and other comments received by the Agency at meetings with industry and

labor groups relative to the ongoing litigation, as well as its own

review of the application of the regulations, MSHA became aware of

several provisions that needed to be further evaluated and analyzed. In

many cases, comments received were verbal. Therefore, any references in

this preamble to ``comments'' or ``commenters'' do not necessarily mean

either written or formal comments. Persons wishing to formalize

comments made during public meetings or other meetings with the Agency

should submit their comments as a part of this rulemaking.

In general, the proposed standards specified below address the

stayed provisions, clarify the Agency's intent, refine the application

of the rule in light of information received, and more fully address

the recognized precautions and procedures necessary to avoid hazards

associated with improper ventilation of underground coal mines. Major

areas addressed include: examinations, including preshift examinations;

recordkeeping and certification; involvement of the representative of

miners in the plan approval process; escapeway dimensions; equipment in

primary escapeways and fire suppression systems. These standards are

intended to fit within the comprehensive structure of the ventilation

rule now in effect.

In addition, a segment of the mining community has asserted that

certain provisions concerning the installation and removal of

mechanized mining equipment were promulgated without the benefit of

adequate comment. The Agency disagrees. The September 1989 explosion at

the William Station Mine in Kentucky demonstrates, however, that proper

ventilation during the installation and removal of mechanized mining

equipment is essential and can greatly enhance the protection provided

to miners in these areas. Therefore, for the purpose of receiving and

giving full consideration to all pertinent comments on this issue, MSHA

is reproposing each provision that addresses the installation and

removal of mechanized mining equipment, and is soliciting comments for

each. The section-by-section portion of the preamble discusses each

provision affected and the proposed rule sets out the reproposed

language.

Since publication of the ventilation rule, the Agency has received

comments stating that Atmospheric Monitoring Systems (AMS) should be

permitted to operate by battery backup during fan stoppages and not be

required to be intrinsically safe. The commenters indicated that the

information thus provided by the AMS would assist the operator in

obtaining information regarding the underground conditions of the mine.

To allow the battery backups would require a revision of

Secs. 75.311(h) and 75.313(e). The Agency solicits comments on the

merits and the effect on safety of allowing battery backups and

conditions, such as low methane levels, that must exist if they are

permitted to be used.

Also, since publication of Sec. 75.383, the Agency has received

comments suggesting that older miners be allowed to individually

decline participation in escapeway drills. The Agency is not proposing

any revision to Sec. 75.383; however, comments are solicited as to the

appropriateness of providing an option which would allow miners to

individually ``opt out'' of escapeway drills, and the circumstances

under which miners would be permitted to ``opt out.''

The Agency solicits comments on the specific provisions addressed

in this proposal. Comments received that also address other provisions

will be considered to the extent that they address the issues relevant

to this proposal.

B. Section-by-Section Discussion

Section 75.301 Definitions

Since the final rule became effective on November 16, 1992, it has

come to the attention of the Agency that the Sec. 75.301 definitions of

intake and return air are being interpreted in a manner not wholly

consistent with the original intent. Under the proposal, the definition

of return air would be modified to more clearly convey the intended

meaning.

Instances have developed where operators desire to take air from an

intake air course to ventilate shops, electrical installations, or for

other purposes, and this air is then coursed directly to the surface

and is not used to ventilate working places. Under one reading of the

existing definition, because this air has not ventilated a working

place or a worked-out area, the air in this air course cannot be

considered return air. Therefore, a violation could exist in that the

air ventilating the shop, compressor, or electrical installation was

coursed into an intake rather than into a return as required. This was

not the intent of the Agency and no safety benefit is associated with

such a result.

Under the proposal, the definition of return air would be modified

to permit operators to designate certain air courses as return air

courses for the purpose of ventilating structures, areas or

installations that are required to be ventilated to return air courses

and for ventilating seals when this air will not be used to ventilate

working places. Thus, an operator wishing to split air off of an intake

for the purpose of ventilating shops, electrical installations, or for

other purposes, could designate the air course into which the split is

directed as a return provided the air in the air course would not used

to ventilate working places or other locations, structures,

installations or areas required to be ventilated with intake air.

The Agency does not intend that operators routinely redesignate air

courses from intake to return. Should questions arise as to the need to

redesignate an intake as a return, MSHA will be available for

consultation. Additionally, in order that all interested parties are

made aware of the redesignation, MSHA is proposing to require in

Sec. 75.372, Mine ventilation map, that air courses that are

redesignated from intake to return for the purposes discussed above be

shown on the mine ventilation map.

Section 75.310 Installation of Main Mine Fans

Main mine fans provide the means by which mechanically produced

pressure is supplied to the mine ventilating current. The Agency is

proposing to revise paragraphs (a)(3), (a)(4) and (c) of Sec. 75.310.

The existing standard requires, in part, that each main mine fan be

installed on the surface in an incombustible housing and be connected

to the mine opening with incombustible air ducts. Paragraph (a)(3) of

existing Sec. 75.310 requires that each main mine fan be equipped with

an automatic device that gives a signal when the fan either slows or

stops. The signal from this device is to be placed so it can be seen or

heard by a responsible person who has been designated by the operator

and who is always on duty when persons are underground.

During informational meetings held with the mining community, it

was suggested to the Agency that the standard should be clarified in

two respects. First, it was stated that the provision was not clear as

to whether the signal must automatically be given at a surface location

at the mine. Second, the Agency was asked to clarify whether a fan

monitoring system used in lieu of a circular pressure recorder to

monitor fan pressure must generate a continuous graph or chart.

To address the first of these concerns, proposed paragraph (a)(3)

specifically would require the signal to be given at a surface location

at the mine where it could be seen or heard by a responsible person

designated by the operator who is always on duty when persons are

underground. Under the proposal, two-way communication with working

sections would continue to be required. The requirement would be

extended to include established locations where persons are normally

assigned to work, such as belt transfer points and shops. This

requirement is consistent with existing Subpart Q--Communications, but

may require the installation of a limited number of mine phones at

locations off the section. Many of these locations are routinely

equipped with two-way communication even though it is not required by

the existing standard. It is not intended that this communications

capability be provided in areas where persons are assigned to work

temporarily, such as areas where secondary roof support is being

installed or where rock dust is being applied. The requirement that

two-way communication be provided to locations where persons are

normally assigned to work is intended to assure that these persons

receive prompt notification of fan stoppages. Because these work

locations are off the section, a lack of communication capabilities

could result in delays in notification and therefore delays in

withdrawal. The requirement that the signal be given at a surface

location at the mine is not intended to preclude the signal from also

being given elsewhere, such as at a central office, as long as it is

given at the mine as previously discussed.

The existing rule requires that each main mine fan be equipped with

a pressure recording device or a main mine fan monitoring system.

Traditionally, the instrument of choice for recording fan operating

pressure has been the mechanical, circular pressure recorder. As the

name implies, this device generates a record of the fan pressure. This

record is generated continuously as a chart that is replaced weekly.

Paragraph (a)(4) of the existing rule specifically refers to the use of

a fan monitoring system as an alternative to the pressure recorder. The

proposal eliminates this reference since other means of continuously

monitoring the fan pressure and providing a record may be acceptable.

Relatively recent advances in technology have permitted the measurement

and recording through other means. This proposed provision would permit

the use of this technology for monitoring main mine fan pressure,

provided, as proposed in paragraph (a)(4), that a continuous record of

the pressure is maintained. The proposal would require that when a

pressure monitoring device is used in lieu of a pressure recording

device, it produce a continuous graph or chart of the fan pressure. A

hard copy of the continuous graph or chart would be printed at regular

intervals of not more than 7 days. The generated graph or chart would

be required to correlate fan pressure to the time and date. The term

``continuous'' refers to the frequency with which the device polls the

fan pressure to obtain the data. It is the Agency's understanding that

typical polling frequency is on the order of a few seconds. MSHA is

soliciting comments as to an appropriate polling frequency that would

provide a record that is substantially continuous.

Records of the fan pressure generated by a pressure monitoring

device would be maintained in accordance with existing Sec. 75.312(h).

That is, the records would be maintained at a surface location at the

mine for at least one year and would be made available for inspection

by authorized representatives of the Secretary and the representative

of miners.

In addition to permitting fan monitoring systems to be used as a

means of recording fan pressure, the existing rule permits the use of

other devices for measuring fan pressure under certain circumstances.

This exception is for mines permitted to shut down main mine fans as

approved in the ventilation plan. As explained more fully in the

preamble for Sec. 75.310(a)(4) of the existing rule, this provision

provides a compliance alternative for small mines that normally operate

only one shift a day and do not have sealed or unsealed worked-out

areas. For these mines, the existing rule allows the use of a pressure

measuring device if the use of the device is approved in the

ventilation plan for the mine. The proposal would continue this

practice.

Paragraph (c) of the existing rule specifies the minimum

requirements for a fan monitoring system, including the parameters that

a fan monitoring system must monitor if it is to be used in lieu of the

daily fan check required by Sec. 75.312. The Agency continues to

support the use of these systems or any other technology effective in

enhancing safety but believes, based on comments received, that the

additional requirements relative to the use of these systems are

warranted. Specifically, commenters suggested that the information

generated by fan monitoring systems be provided at a surface location

at the mine where a responsible person is always on duty when persons

are underground and that this information be reviewed by mine

management. The Agency agrees with these suggestions and proposes in

paragraph (c) to require that when a fan monitoring system is used in

lieu of the daily fan examination required by Sec. 75.312 the

monitoring system would be required to have the capability of

providing, on demand, a printout of the information being monitored.

This capability is intended to facilitate the review of the information

by mine management required in Sec. 75.312(b).

Additionally, the proposal would require in paragraph (c)(5) that

the fan monitoring system provide monitoring, records, printouts, and

signals at a surface location at the mine where a responsible person

designated by the operator is always on duty and where signals from the

monitoring system can be seen or heard while anyone is underground. For

the purpose of the standard, a responsible person would be one who

receives the signal and makes proper notification. As with the

requirement that fan stoppage signals be given at a surface location at

the mine, this proposed requirement is not intended to preclude the

data from the fan monitoring system from also being provided elsewhere

as long as it is provided at the surface location at the mine. Also, as

with the requirement for two-way communication at the location where

fan stoppage signals are monitored, the proposal would require in

paragraph (c)(5) that the person at the designated surface location

have two-way communication with working sections and would extend the

requirement to established locations where persons are normally

assigned to work, such as belt transfer points and shops. This

requirement is consistent with existing Subpart Q--Communications, but

may require the installation of a limited number of mine phones at

locations off the section. Many of these locations are routinely

equipped with two-way communication even though it is not required by

the existing standard. It is not intended that this communications

capability be provided in areas where persons are assigned to work

temporarily, such as areas where secondary roof support is being

installed or where rock dust is being applied.

Section 75.311 Main Mine Fan Operation

The Agency has received comments that notification of mine

management officials, having sufficient authority to initiate

corrective actions is needed to assure that repairs are undertaken and

to assure continued reliable ventilation of the mine. Paragraph (d)

would be revised to provide for immediate notification of the mine

superintendent, assistant mine superintendent, or mine foreman if any

unusual variance in the mine ventilation pressure is observed, or if an

electrical or mechanical deficiency of a main fan is detected. The

standard would require appropriate action or repairs to be instituted

promptly. The Agency would expect that any necessary arrangements for

repair personnel and replacement parts would be promptly completed,

once the problem or need for repair was identified. One of the actions

appropriate to an unusual variance in pressure would be an immediate

investigation into the cause. Notification of mine management is

intended to assure that the appropriate actions are taken and that any

necessary repairs are completed as soon as possible. Both the

requirement for notification of mine management and the requirement for

prompt initiation of corrective actions were included in the previous

regulation. Although no change was intended, it was suggested that

these requirements be reinstated so as to eliminate any possible

confusion that might exist. After reconsideration, the Agency agrees

that the existing standard could be interpreted contrary to the intent

and therefore, is proposing the changes discussed. Since the current

ventilation standards became effective on November 16, 1992, questions

have arisen concerning the operation of back-up fans. The following

discussion is intended to address the questions received by the Agency.

When a back-up fan operates in place of the main mine fan, the

back-up fan is considered to be a main mine fan and all subpart D

requirements for main mine fans are applicable. These requirements

include: the installation requirements of Sec. 75.310, the operation

requirements in this Sec. 75.311, the examination and recordkeeping

requirements of Sec. 75.312, and, the unintentional fan stoppage

requirements of Sec. 75.313, which would apply should a back-up fan

fail while persons are underground.

A typical back-up fan application is where a back-up fan producing

an air quantity comparable to the main mine fan is substituted upon the

unintentional failure of the main mine fan. Section 75.313 would

require withdrawal of the miners if the backup fan, or main mine fan,

is not started within 15 minutes. If the back-up fan is started within

15 minutes, however, normal work may resume after an examination, since

the air quantity would be provided. An example would be two identical

fans at a shaft where one operates as the main mine fan while the other

is available to back up the main mine fan. Typically, the usage of

these fans is alternated.

Another possible application is a back-up fan producing a lesser

quantity than the main mine fan. In this case, unless the main mine fan

can be restored to operation within 15 minutes, withdrawal would be

required under Sec. 75.313. After withdrawal is complete, re-entry

could be permitted and electrical circuits restored as provided through

the approved ventilation plan. The Agency would expect operators to

rely on engineering data or actual ventilation survey results when

developing these ventilation plan provisions. During operation of the

back-up fan, the approved ventilation plan would only permit activity

which is related to maintaining the mine in safe condition. This work

could include pumping, urgent roof support installation, or other

safety-related work. The production of coal under these conditions

would not be permitted unless the mine were adequately ventilated and a

new ventilation plan has been approved.

Some multiple-fan ventilation systems are configured such that if

one fan fails, reduced air quantities continue to ventilate all

portions of the mine with no potentially hazardous air reversals

occurring. In such cases, ventilation plan provisions, if supported by

data, could be developed which would allow re-entry for the purposes

discussed in the previous paragraph. This activity would be limited to

maintaining the mine in safe condition until the full ventilation

system is restored to operation.

Under existing Sec. 75.311(b)(1), when a main mine fan is stopped

intentionally and the ventilating quantity of the main mine fan is not

maintained by a back-up fan, only persons necessary to evaluate the

effect of the fan stoppage or restart, or to perform maintenance or

repair work that cannot otherwise be made while the fan is operating,

are permitted underground. The maintenance or repair work which could

not be made while the fan is operating is limited to work or repair

which would endanger the safety of the worker if the fan were

operating. Examples of the type of work that may not be possible while

the fan is operating could include maintenance of the fan, repairs or

adjustments to ventilation controls immediately inby the fan that are

subject to high pressure differentials, and coating of mine surfaces

immediately inby the fan. These examples are given for the purpose of

facilitating understanding and are not considered all-inclusive.

While the Agency is proposing to change only paragraph (d) of

existing Sec. 75.311, comments are specifically solicited on the issues

discussed.

Section 75.312 Main Mine Fan Examinations and Records

The Agency would revise the existing standard in a number of

respects. Except in certain situations, a daily examination of the main

mine fans would be required each day that the mine operates. One

exception would be the use of a fan monitoring system in accordance

with Sec. 75.312. Requirements for training, recording of defects,

review of fan monitoring data, certifying and countersigning of records

would be added to the rule. Also, the standard would allow underground

power to remain energized when a fan is shut down for testing of the

automatic closing doors and fan signal device, provided that the fan is

restarted within 15 minutes, and would permit an alternative means of

testing that would not require stopping the fan.

Proper operation of main mine fans is critical to mine ventilation.

Paragraph (a) of the proposed rule, like the existing standard,

requires main mine fans and associated components, including devices

used to measure and record pressure, to be examined at least once each

day that the fan operates, unless a functioning fan monitoring system

is used. However, it is proposed that on any day when no one goes

underground that a fan examination would not be required. The Agency is

proposing this approach along with the provision that an examination of

the fan be completed prior to anyone's entering the mine, including

certified persons. Such an examination would assure that the fan is

operating properly. The Agency does not believe that any hazard can be

associated with not examining a mine fan if no one goes into the mine,

and solicits comments on this point.

During the informational meetings and later discussions, the Agency

was asked to clarify the qualifications of the person designated by the

operator to make daily fan examinations or the weekly fan examination

in the case of mines using fan monitoring systems. It continues to be

the position of the Agency that persons assigned to make this or any

other examination must be capable of making an adequate examination;

that is, an examination in a manner that assures the protection sought

by the standard. For this reason, and to address the concerns raised,

the proposal would adopt the words of the regulation in effect prior to

November 16, 1992, Sec. 75.300-4(a), and require in paragraphs (a) and

(b)(1) that main mine fans be examined by trained persons designated by

the operator. Since the purpose of the examination, as stated in the

proposed standard, is to assure the electrical and mechanical

reliability of the fan, the training that the examiner receives should

be focused on the electrical and mechanical functioning of fans.

The proposal, in paragraph (b)(1)(i), reflects comments received by

the Agency that in order for fan monitoring systems to be effective,

the data from these systems must be reviewed by mine management each

day. This review is intended to parallel the daily fan examination and

assure that responsible personnel are aware of the performance of the

fan and the fan monitoring system. In paragraph (b)(1)(ii), the

proposal would retain the requirement that at least once every 7 days

the monitoring system be tested and the main mine fan be examined.

Consistent with paragraph (a), as discussed previously, this

examination would be required to be done by a trained person designated

by the operator for the purpose of assuring the electrical and

mechanical reliability of the fan.

During the informational meetings and later discussions, the Agency

was also requested to clarify the application of paragraph (c) of this

standard. Some of the comments concerned whether underground electrical

circuits must be deenergized while tests of fan signal devices and

automatic closing doors are performed. Questions also arose as to

whether anyone could be in the mine during the tests and whether a

complete Sec. 75.360 preshift examination is required following the

tests before anyone could enter the mine.

The proposal clarifies the Agency's intent in paragraphs (c) and

(d) of the existing Sec. 75.312. The 31-day tests are to determine if

the alarm activates properly and, in multiple-fan systems, whether the

automatic doors, if required, close. Although fan stoppages for these

tests are normally of short duration, it must be recognized that on

rare occasions difficulty may be encountered in restarting the fans.

Therefore, the Agency has determined that it is not advisable to allow

miners underground during tests when the fan is stopped unless

concurrent activities are scheduled that are necessary to evaluate the

effect of the fan stoppage or restart, or to perform maintenance or

repair work that cannot otherwise be done while the fan is operating.

Another commenter continued to express concern that monthly

stoppage of fans for testing can cause undue stress on the fans. MSHA

has received assurances from fan manufacturers that stopping the fans

monthly to test the signal device will not cause undue stress on fans.

The Agency has also recently received assurances from motor

manufacturers that monthly stoppage of fans will not harm fan motors.

The Agency solicits comments on this issue as well as on any other

aspect of paragraphs (c) and (d).

The Agency has received requests for clarification as to whether

fans stopped for testing must be completely stopped during the 31-day

tests. The purpose of the standard is to assure proper operation of the

alarm and doors when a fan fails. Under certain conditions, such as

with a substantial natural ventilating pressure, the fan blades may

continue to rotate indefinitely. However, after power has been removed

and the fan is in the process of stopping, once the alarm sounds and

the doors close, the test has been successfully completed and the fan

may be restarted even though the fan blades may not have become

motionless.

Recognizing that the duration of these tests is normally short, the

proposal does not require underground electrical circuits to be

deenergized unless the fan cannot be restarted within 15 minutes or

unless persons are permitted underground in accordance with

Sec. 75.311(b)(1). In accordance with longstanding practice, as

indicated by a review of fan stoppage plans and consistent with

existing Sec. 75.313, an examination as described in Sec. 75.360 (b)

through (e) would be required if the fan is not restarted within 15

minutes. The Agency believes that after 15 minutes, additional action

is needed to protect miners from the hazards that may develop following

a fan stoppage.

Following publication of the existing standard, commenters

suggested that it may be possible to test the fan signals and the

automatic closing doors without shutting off the fans. If it is

possible to properly test the fan signal and automatic closing doors

without stopping the fan, then the Agency would permit such an

alternative. The Agency has become aware that such an approach is being

actively explored by at least one mining company. Therefore, in the

interest of allowing for advances in technology in this area, the

proposal would permit an alternative test that does not require

stopping the fan when the operator demonstrates that it provides the

same level of assurance that the automatic closing doors and fan

signals will function as intended during fan stoppages. Alternative

approaches to stopping the fan would be required to be approved in the

ventilation plan. The Agency would anticipate that any alternative

approach approved would retain the 31 day interval for demonstrating

that the automatic closing doors or fan signal will operate as

intended. The Agency solicits comments on this approach to fan tests.

Specifically, comments should address the method that should be used to

assure that the alternate test provides the same level of assurance

that the automatic closing doors and fan signals will function as

intended during fan stoppages.

Paragraph (f)(1) retains the requirement in the existing rule that

persons making main mine fan examinations certify by initials and date

at the fan or another location specified by the operator, that the

examinations were made, and that each certification identify the main

mine fan examined. Consistent with the practice of certifying that fan

examinations have been completed, the Agency is proposing a

certification requirement in paragraph (f)(2). The person completing

the review of the data from a fan monitoring system used in lieu of

daily fan examinations would certify that the review has been

completed. The manner of certification would be by initials and date on

the printout of the data from the system. To facilitate this

certification, proposed Sec. 75.310(c)(3), as discussed previously,

would require that the fan monitoring system be capable of providing,

on demand, a printout of the data.

Proposed paragraphs (g)(1) through (g)(5) would set out the

requirements for recordkeeping and countersigning of main mine fan

examination records. Paragraph (g)(1) would require that by the end of

the shift on which the examination is made, persons making main mine

fan examinations would record all defects found during the examination

that may affect the operation of the fan. Unlike the previous standard,

the existing standard requires that only defects that are not corrected

by the end of the shift be recorded. The preamble to the existing rule

explains this approach as follows: ``* * * since the main purpose of

this recordkeeping requirement is to alert miners on oncoming shifts of

defects found during the fan examination that may affect their shifts,

it serves no additional safety benefit to require a record to be made

of deficiencies which are corrected by the end of the shift on which

the examination is made.'' However, following publication of the

standards, the Agency received comments that records of defects,

corrected or not, serve to indicate recurring problems with mine fans.

Upon reconsideration, MSHA agrees that recurring problems found during

main mine fan examinations may be indicative of more serious defects

and if mine management is not made aware of these problems through the

maintenance of records they could ultimately lead to a fan failure.

Therefore, similar to the previous standard, the proposal would require

that all defects found during the daily fan examination be recorded. As

with other proposed provisions of the rule, records required in

paragraphs (g)(1) through (g)(4) would be made in a state-approved book

or in a bound book with sequential machine-numbered pages. Comments are

specifically solicited on this approach and on an alternative approach

wherein the Agency would develop, in coordination with the states,

books specific for the required records.

Since promulgation of the current regulation, the Agency has become

aware of some potential difficulties in reviewing records and data

generated by fan monitoring systems and atmospheric monitoring systems.

The problem involves the commingling of this information with other

information, such as production or operations-related data produced by

the computer systems of which they are a part. Since the physical

volume of production, operations, and other data may be considerable,

safety-related data may not be readily accessible which may discourage

the regular review and proper use of the information. A possible

solution is to require that all safety related data be printed on a

dedicated printer. The Agency is not proposing this solution at this

time but rather is soliciting comments on possible alternative

solutions. At this time, the Agency is proposing, in paragraph

(g)(2)(i), that the certified copies of data required by paragraph

(f)(2) be maintained separate from other computer generated reports or

data in order to facilitate the review of this data by the operator,

the representative of miners, and the Agency.

Proposed paragraph (g)(2)(ii) would require a record to be made of

any fan monitoring system malfunctions, electrical or mechanical

deficiencies in the monitoring system and any sudden increase or loss

in mine ventilating pressure. The records would be used to identify

chronic or recurring problems with the system that could indicate the

need for repairs, replacement of parts, or upgrades in hardware or

software in order to keep the system functioning in a reliable manner.

The record would be required to be made by the end of the shift on

which the review of the data is completed. This requirement would help

to assure that records are current and that potential problems are

identified in a timely manner.

Consistent with existing requirements, paragraph (g)(3) would

require that at mines permitted to shut down main mine fans under

Sec. 75.311, if a pressure recording device is not used, a record be

made of the time and fan pressure immediately before the fan is

stopped, and after the fan is restarted and the fan pressure

stabilizes. A record of these pressures at both shutdown and restart

would help identify any adverse change in ventilation that may have

occurred during the fan stoppage.

Paragraph (g)(4) would require that a record of the results of the

tests be made by the end of the shift on which the monthly test of the

automatic fan signal device or the automatic closing doors is

completed. This requirement would help to assure that potential

problems are identified in a timely manner so that proper operation of

the automatic fan signal device and the automatic closing doors can be

maintained.

Paragraph (g)(5) would require that the records required under

paragraphs (g)(1) through (4) be countersigned by the mine foreman by

the end of the mine foreman's next regularly scheduled working shift.

During an absence of the mine foreman, the person acting as mine

foreman would countersign. The Agency intends that the mine foreman,

the person most responsible for the day-to-day operation of the mine,

be notified of the information contained in the reports. Allowing until

the end of the mine foreman's next regularly scheduled working shift to

countersign the report would assure that the mine foreman is aware of

the results of the examination and would enable corrective actions to

be taken.

The proposal would also require that within two scheduled

production days after the mine foreman has countersigned, the record of

the examination be countersigned by the mine superintendent, mine

manager, or other mine official to whom the mine foreman is directly

accountable. The intent of the proposal is to assure that a higher

level official, empowered to redirect resources, be aware of any

condition requiring corrective actions. Since this second level

official may not be physically located at the mine on a full-time

basis, two scheduled production days are proposed as a reasonable

period of time for countersigning.

Section 75.313 Main Mine Fan Stoppage With Persons Underground

This standard establishes safety precautions for any unplanned main

mine fan stoppage that interrupts ventilation while persons are

underground. Paragraph (a)(3) requires all persons to be withdrawn from

working sections and areas where mechanized mining equipment is being

installed or removed when ventilation is interrupted by a main mine fan

stoppage. Areas where coal is being extracted or mechanized mining

equipment is being installed or removed are typically the places in an

underground mine where methane accumulation and other hazards to health

or safety can develop quickly when ventilation is interrupted. To avoid

exposure of miners to these hazards, timely withdrawal of persons is an

important safety practice. Although the Agency believes that the

promulgation of paragraph (a)(3) of this standard was done

appropriately, it is being reproposed for the purpose of receiving and

giving consideration to all pertinent comments.

Concerns have been raised about the possibility of methane

migration following fan stoppage, and the danger of using electrical

power to withdraw miners should this occur.

The proposal would revise stayed Sec. 75.313(c)(2) and (c)(3) which

address deenergization of electric power circuits and shutting-off of

mechanized equipment not located on working sections. It also would

revise paragraph (d)(1)(i) and (ii) and (d)(2) which deal with

examination of the mine before miners can return when power is

restored. The Agency is not proposing a revision of paragraphs (a),

(b), (c)(1), and (e) at this time. These paragraphs of stayed

Sec. 75.313 would remain unchanged from the stayed provision.

Under paragraph (c)(2) of the proposal, underground electrical

circuits must be deenergized, except those circuits necessary for

withdrawal if such circuits are located in areas and haulageways where

methane is not likely to migrate into or accumulate. The remaining

energized circuits would be deenergized as persons are withdrawn. The

Agency recognizes that in a limited number of mines methane may migrate

from adjacent areas and enter travelways or haulageways used by miners

for withdrawal. Under these conditions, permitting power circuits to

remain energized may increase the potential for a methane ignition. The

determination of the likelihood of methane migrating into haulageways

can be made through underground tests or computer simulations of

ventilation systems. It is the intention of the Agency that when it is

determined that methane is likely to accumulate or migrate into an

area, electrical circuits used for transportation would not be

permitted to remain energized and persons would not be permitted to

ride out of the mine in the event of a fan stoppage. The Agency would

expect the operator to provide the necessary data from which a

determination can be made. For the same reasons, paragraph (c)(3) of

the proposal would require mechanized equipment not located on working

sections to be shut off unless the equipment is necessary to withdraw

persons from the mine and is located in areas where methane migration

or accumulation is unlikely to occur. The Agency solicits comments on

the appropriateness of this type of mine-specific evaluation that

balances the expeditious withdrawal of miners against the potential for

methane accumulations.

Under paragraphs (d)(1)(i) and (ii) of the proposal, the Agency is

clarifying that when ventilation is restored and before electrical

circuits are energized or nonpermissible mechanized equipment is

started, no one other than designated certified examiners would be

permitted to enter or reenter any underground area of the mine until an

examination is conducted as described in Sec. 75.360(b) through (e) and

the area is determined to be safe. This would prohibit nonpermissible

mechanized equipment from being started until an examination is

completed. However, permissible equipment may be used to facilitate the

examination required by the proposal. The Agency recognizes that it may

not be possible for examiners to enter the mine without some power

being restored in shafts or slopes to power elevators, hoists, or other

mechanical facilities operated in the shaft or slope. The Agency does

not intend to prohibit these facilities from being energized when used

to facilitate the examination, provided they are in intake air and the

power is limited to the shaft or slope in which they operate. The

Agency solicits comments on this approach to fan stoppages.

This examination would not be equivalent to a full-scale preshift

examination in that (1) a preshift is conducted within 3 hours

preceding the beginning of the shift, and (2) the recordkeeping

requirements of Sec. 75.360 would not apply for the examination

following a fan stoppage. However, in accordance with proposed

Sec. 75.363, a record of all hazardous conditions found would be

required. This type of examination is an accepted safety practice in

the industry. It is a primary means for determining the effectiveness

of a mine's ventilation system and of detecting hazards such as methane

accumulations that may be present in travelways or other areas where

miners may work after an interruption of ventilation. After a fan is

restarted, the examination will determine if the air is moving in its

proper direction and at its normal volume.

The Agency has reconsidered its position in stayed

Sec. 75.313(d)(2) and proposed in paragraph (d)(2) to specifically

require miners, other than designated certified examiners, to continue

to the surface should the fan restart during withdrawal. A commenter

has maintained that following a fan stoppage, a hazard could occur due

to methane accumulations, and therefore miners should not be permitted

to remain underground. MSHA agrees that such methane accumulations

could occur, but believes that any risk of ignition would be

significantly reduced by the requirement that mechanized equipment be

shut off and electrical power circuits deenergized except for equipment

and power circuits necessary for withdrawal if located in areas or

haulageways where methane is not likely to migrate to or accumulate.

Under stayed Sec. 75.313, the equipment or circuits used for withdrawal

must be shut off or deenergized as persons are withdrawn. However, to

provide an added margin of safety, MSHA is proposing withdrawal of all

miners to the surface except designated certified examiners who may

begin the examination required before miners return to underground

areas. The Agency specifically solicits comments on this issue.

This commenter further stated that when a fan is down for an

extended period of time, a fan should not be restarted until miners

safely reach the surface. However, as stated in the preamble to the

existing rule, MSHA believes that the fan should be restarted as soon

as possible to reestablish proper ventilation and to remove the

potential for methane accumulations. The Agency solicits comments on

the pros and cons of reestablishing ventilation by restarting a mine

fan during evacuation, and on having miners continue to the surface

should a fan restart during withdrawal.

Additionally, the proposal would require that an examination be

made as described in Sec. 75.360(b) through (e). Although complete

withdrawal of miners is required, this examination could begin once

ventilation has been restored and would be performed by certified

persons designated by the operator to conduct the examination. The

Agency is proposing this approach because of the safety concerns

associated with extended interruptions in the ventilation system. It is

recognized that under Sec. 75.360(a) a preshift examination can be made

for an oncoming shift while miners are underground. However, the

proposal would not allow miners to remain underground because of the

lack of ventilation compared to the situation where ventilation is

continuously maintained.

Section 75.320 Air Quality Detectors and Measurement Devices

The informational meetings and later discussions on the rule

indicated that simply requiring detectors for measuring methane and

oxygen deficiency to be maintained in permissible condition does not

completely satisfy the need for assuring proper maintenance. It was

suggested that without a requirement for maintenance to be done by a

trained person, similar to that which existed in the previous standard,

a person with less than the necessary understanding of the instrument

and the permissibility requirements might be assigned the task. The

proposal would require that methane detectors and other devices be

properly maintained at all times and, to assure the appropriate level

of maintenance, the proposal in paragraph (e) would require this

maintenance to be done by a trained person. This does not preclude the

operator from sending instruments to the manufacturer or another repair

facility for regular servicing.

Additionally, the proposal would require the operator to assure

that any instrument sent underground is in permissible condition so

that the use of the instrument does not pose an explosion hazard. The

level of care that must be exercised is of course a function of

instrument usage but, at a minimum, the Agency would expect that the

detector be visually examined to assure that it is properly assembled

and that all necessary components such as screws, lenses, and indicator

lamps are present. As with the requirement that maintenance be done by

a trained person, this requirement was present in the previous standard

and is being proposed to further assure that methane detectors do not

pose a hazard and will perform properly during the shift.

Section 75.321 Air Quality

This proposal would continue a basic air quality requirement that

has been in place since 1970 that air in areas where persons work or

travel contain at least 19.5 percent oxygen and not more than 0.5

percent carbon dioxide, and the volume and velocity of the air current

in these areas be sufficient to dilute, render harmless, and carry away

flammable, explosive, noxious, and harmful gases, dusts, smoke, and

fumes. The proposal would not require this carbon dioxide level to be

applied to bleeder entries and worked-out areas.

MSHA has interpreted former Sec. 75.301 to require at least 19.5

percent oxygen and no greater than 0.5 percent carbon dioxide in

bleeder systems where persons work or travel. Similarly, it was the

intent of the Agency to enforce Sec. 75.321 to require compliance with

these levels where persons would be exposed in bleeder entries and in

worked-out areas. However, the application of this provision to

bleeders has been stayed by the D.C. Circuit pending the outcome of

litigation on the rule. The Agency continues to believe that providing

satisfactory air quality is essential to protect the miners and

examiners whenever they work or travel in bleeder entries and worked-

out areas. Therefore, the proposal includes a new provision specifying

that the air in bleeder entries and worked-out areas where persons work

or travel contain at least 19.5 percent oxygen, and that carbon dioxide

not exceed 0.5 percent TWA (Time Weighted Average) and 3.0 percent STEL

(Short Term Exposure Limit). A TWA is the time-weighted average

concentration for a normal 8-hour workday and a 40-hour workweek. A

STEL is a 15-minute TWA exposure which can not be exceeded at any time

during a workday even if the 8-hour TWA is within the specified TWA.

Exposures above the TWA up to the STEL can not be longer than 15

minutes and can not occur more than four times per day. There must be

at least 60 minutes between successive exposures in this range. These

proposed levels are identical to the levels contained in MSHA's

proposed air quality standards for coal and metal and nonmetal mines

and the 1992 Threshold Limit Values (TLV) as specified by the American

Conference of Governmental Industrial Hygienists.

In light of the ongoing air quality rulemaking, the Agency is not

at this time proposing to modify existing air quality standards as

applied to areas where persons work or travel, other than bleeder

entries and worked-out areas. The Agency will consider the appropriate

course of action on this issue as part of the air quality rulemaking.

Bleeder entries and worked-out areas are required to be traveled or

evaluated at least weekly. This is most often done by a person

traveling alone who is often required to be in the bleeder entries or

worked-out areas for an extended period. The purpose of this standard

is to protect miners, not to regulate air quality where persons are not

exposed. Therefore, oxygen and carbon dioxide levels at bleeder

connectors and bleeder evaluation points that do not meet the proposed

concentrations would not constitute a violation of the standard if

examinations are performed remotely or if persons making the

examination can otherwise remain in air that meets the proposal.

According to the National Institute for Occupational Safety and

Health (NIOSH) of the U.S. Department of Health and Human Services

(NIOSH Respirator Decision Logic, May 1987), 19.5 percent oxygen

provides an adequate amount of oxygen for most work assignments and

incorporates a safety factor. Also according to NIOSH, the safety

factor is needed because oxygen-deficient atmospheres offer little

warning of danger. In the NIOSH publication, ``A Guide to Safety in

Confined Spaces,'' (page 4), a chart is presented that indicates that

19.5 percent oxygen is the minimum level for safe entry into an area,

and that at a level of 16 percent, judgement and breathing are

impaired. The American National Standards Institute (ANSI), in ANSI

Z88.2-1992, ``American National Standard for Respiratory Protection''

recognizes that at 16 percent oxygen there is an impairment in the

ability to think and pay attention, and a reduction in coordination.

ANSI recognizes that at 19 percent oxygen there are some adverse

physiological effects, but they are unnoticeable.

The need for regulating the oxygen level where persons work or

travel in bleeder entries is illustrated by two mining accidents. One

of these accidents resulted in the death of a mine examiner and the

second resulted in the near death of two additional individuals, one of

whom was a mine examiner. Mine examiners are, through training and

experience, the individuals best able to identify the hazards

associated with irrespirable atmospheres. The first accident occurred

at the Arclar Mine in Equality, Illinois in 1989. Prior to

implementation of the existing standard, a mine examiner, for unknown

reasons, entered a worked-out area that was posted with a danger sign.

Under the existing regulation, ventilation or sealing of this area,

rather than posting, would be required. Because the area was not

sealed, the existing regulation would require the area to be examined

during the weekly examination. The proposal would require that the

route of travel for the examiner would contain at least 19.5 percent

oxygen. Had the proposal been in place when the examiner entered the

worked-out area, there is a strong likelihood that he would not have

died.

The second accident, although not in a bleeder entry or worked-out

area, is illustrative of what can happen when individuals, including

mine examiners, are subjected to oxygen deficient air. In 1983 at the

Bird No. 3 Mine in Riverside, Pennsylvania, an assistant mine foreman,

a certified person, entered the mine for the purpose of conducting an

examination. After traveling approximately 1100 feet, the examiner

became dizzy, noticed that his flame safety lamp had extinguished and

withdrew approximately 200 feet where he sat down and apparently became

unconscious. A second individual upon entering the area in search of

the examiner also became dizzy but was able to withdraw to a location

that was not oxygen deficient. When the mine examiner regained

consciousness, his cap lamp battery had discharged and he traveled in

total darkness until he encountered a mine rescue team. Air samples

collected in the area where the mine examiner first became dizzy

indicated an oxygen concentration of about 16.8 percent, while other

samples collected nearby indicated oxygen concentrations of nearly 20

percent.

Because mine examiners are required to work or travel in areas

where oxygen-deficient air could occur without warning, and they

normally travel and work alone, there must be a requirement that

provides them the protection necessary for the performance of their

duties under these conditions. It is important that the level for

oxygen be established above that identified as resulting in impaired

judgement because it is essential that individuals traveling in these

areas remain highly alert. The hazards that can exist in bleeder

entries and worked-out areas include elevated methane levels, poor

footing, loose and unstable roof, and water accumulations. For this

reason, the Agency is proposing to adopt a minimum level of oxygen of

19.5 percent as recommended by NIOSH.

MSHA is also concerned with the effects of other gases often found

in bleeder entries. Section 75.322 of the existing regulation limits

the concentration of noxious or poisonous gases to the current (1971)

Threshold Limit Values (TLV's) as adopted and applied by the American

Conference of Governmental Industrial Hygienists (ACGIH). Section

75.322 specifically excludes carbon dioxide since it is covered by

Sec. 75.321. However, in light of the Court's stay of Sec. 75.321(a)

relative to bleeder entries, the Agency is proposing a separate

standard for carbon dioxide levels for areas where persons work or

travel in bleeder entries and worked-out areas. The levels proposed,

0.5 percent TWA and 3.0 percent STEL, when considered in conjunction

with the requirements of Sec. 75.322 and the proposed requirement for

oxygen, will aid in providing persons working or traveling in these

areas with a safe and healthful working environment. The Agency

recognizes that the effects of carbon dioxide are both chronic and

acute and has therefore elected to propose both a time weighted average

and a short term exposure limit. NIOSH, in recommending a standard for

carbon dioxide, also recognized this and recommended a similar

approach. The NIOSH recommendation, made in a Criteria Document

published in 1976, proposed a TWA concentration of 1.0 percent and a

ceiling value of 3.0 percent not to exceed 10 minutes. In making this

recommendation, NIOSH states that there are ``additive stress effects

of increased carbon dioxide concentrations and exercise * * *'' As

support for this, the NIOSH document cites research that showed that

healthy, trained subjects exposed to 2.8 to 5.2 percent carbon dioxide

at maximum exercise levels experienced respiratory difficulty, impaired

vision, severe headache, and mental confusion; three subjects

collapsed. At or below 2.8 percent carbon dioxide combined with lower,

but still strenuous, levels of exercise, no ill effects other than

awareness of increased ventilation were experienced by the subjects.

During rulemaking on the proposed air quality standard, NIOSH

recommended a 0.5 percent TWA and a 3.0 percent STEL. NIOSH made a

similar recommendation to OSHA during that Agency's permissible

exposure limit (PEL) rulemaking. Given the work environment in bleeder

entries and worked-out areas, as described earlier, the Agency believes

that the dual regulatory approach proposed is appropriate. In addition

to examiners, other miners may be required to work in the bleeder

entries and worked-out areas, performing duties such as installing roof

support, pumping water, recovering materials or adjusting ventilation.

The levels proposed would provide them with the necessary protection.

In addition, MSHA is concerned with the synergistic effects that

carbon dioxide has on the body when combined with low oxygen levels,

especially at levels higher than 0.5 percent TWA. Carbon dioxide

affects the blood pH, which is critical to the proper metabolism of

oxygen. Because of the nature of the hazardous work environment in

bleeder entries and worked-out areas, the Agency believes that it must

be careful to establish levels which would not impact on the body's

ability to deal with the conditions encountered. The Agency solicits

comments on the appropriateness of these, or other concentration levels

for carbon dioxide in areas where the examiner works or travels in

bleeder entries and worked-out areas, along with the rationale for

determining the appropriate level for bleeder entries and worked-out

areas. However, as stated previously, it is not the intent of the

Agency that the levels established in paragraph (2) of the proposed

standard be applied to areas other than those areas within the bleeder

entries and worked-out areas where persons work or travel. In light of

this, it is not anticipated that many of the nation's coal mines would

be required to increase the volume of air currently being used to

ventilate bleeders and worked-out areas as a result of this proposed

standard.

Section 75.323 Actions for Excessive Methane

MSHA is proposing to revise paragraphs (b)(1)(ii), (c)(1), and

(d)(2)(i) of the existing standard in response to comments made during

informational meetings and subsequent discussions.

Methane poses a significant hazard to miners when it is permitted

to accumulate without corrective action being taken quickly. The Agency

received comments at its informational meetings asking MSHA to clarify

when ventilation changes must be made to reduce methane concentrations

to acceptable levels. MSHA has always intended that these changes be

made at once. In response to these comments, the Agency is proposing to

revise paragraphs (b)(1)(ii), (c)(1) and (d)(2)(i) to require that

these changes be made ``at once,'' the phrase used in former

Secs. 75.308 and 75.309.

Although the Agency believes that the promulgation of paragraph (b)

of this standard was done appropriately, it is being reproposed with

the addition of the phrase ``at once'' for the purposes of receiving

and giving consideration to all pertinent comments. When 1.0 percent or

more methane is present in a working place, an intake air course, or an

area where mechanized mining equipment is being installed or removed,

paragraph (b)(1) would require all electrical, diesel, and battery-

powered equipment in the affected working place, intake air course or

other area, except for intrinsically safe AMS, to be deenergized or

shut off. Deenergizing or shutting off this equipment would protect

miners by preventing this equipment from providing ignition sources.

If 1.5 percent methane or more is present in a working place, an

intake air course, or an area where mechanized mining equipment is

being installed or removed, paragraph (b)(2) would require persons to

be withdrawn from the affected area. The basic requirement for

withdrawal of persons is retained from the previous standard and the

reproposal would expand this basic requirement to include areas where

mechanized mining equipment is being installed or removed. The presence

of methane in these areas can pose a significant risk to miners and

therefore their withdrawal from the affected area is essential to their

safety. Paragraph (b)(2) would also require that all electric power to

equipment in affected areas be disconnected at the power source. This

prevents accidental reenergization of equipment and removes power from

cables and circuits which may also be ignition sources. No other work

is permitted in the affected area until the concentration of methane is

less than 1.0 percent.

Paragraph (b)(2) would be amended by adding ``mechanized'' before

mining equipment for consistency with other provisions of the rule.

Section 75.324 Intentional Changes in the Ventilation System

MSHA is not proposing any changes to the wording of Sec. 75.324 at

this time. The following discussion clarifies MSHA's interpretation of

what the Agency considers to be an intentional change that could

materially affect the safety or health of persons in the mine.

Paragraph (a) of the existing rule requires that a ventilation

change be supervised by a person designated by the mine operator when a

change in section ventilation is in excess of a specified quantity or

when a ventilation change alters the main air current of the mine or

any split of the main air current in a manner that could materially

affect the safety or health of miners underground. Paragraph (b) of the

existing rule specifies additional requirements that apply only to the

ventilation changes described in paragraph (a) of this section. That

is, before such an intentional air change is made, electric power must

be removed from areas that may be affected by the change and mechanized

equipment in those areas must be shut off. Also, only persons making

the ventilation change are permitted in the mine while the change is

being made. Afterward, certified persons must examine the areas

affected by the change to determine whether methane accumulations or

oxygen deficiencies have resulted. Electric power is not permitted to

be restored to affected areas nor is mechanized equipment to be

restarted until these tests have been made and the areas are determined

to be safe.

Since this standard went into effect in November 1992, the Agency

has become aware of concerns suggesting that it is sometimes difficult

to determine whether an intentional change in the air current could

materially affect the safety or health of miners. However, MSHA regards

it as impractical to follow a ``cookbook'' approach to identifying what

will or will not require approval. Each circumstance is to be reviewed

by the operator on its own merits. To illustrate the Agency's

expectations, the following is a list of some examples of what MSHA

considers intentional changes that would materially affect the safety

or health of miners. These examples are not meant to include all

possibilities, but are meant to provide some general guidance: adding a

new shaft; bringing a new fan on line; changing the direction of air in

an air course; changing the direction of air in a bleeder system;

shutting down one fan in a multiple fan system; starting a new

operating section with ventilating quantities redistributed from other

sections of the mine; changing entries from intakes to returns and vice

versa; and any change that affects the information required by

Sec. 75.371, Mine ventilation plan; contents.

The results of changes to a complex ventilation system are not

always easy to predict, and for that reason caution must be used when

making significant changes to one air split or several air splits. The

balance of splits can be affected and may result in air reversals, dead

air spaces, or insufficient air flow in critical areas. For this

reason, such changes must be evaluated by a certified person examining

the affected areas before production is resumed. Approval is required

by paragraph (c) of Sec. 75.370 Mine ventilation plan; submission and

approval, if the change alters the main air current in a manner that

could materially affect the safety or health of miners. When questions

arise as to whether an anticipated change requires prior approval, MSHA

is available to discuss the situation for guidance on whether a request

for approval should be submitted. While the Agency is not contemplating

a change to Sec. 75.324 at this time, comments are specifically

solicited on the issues discussed.

Section 75.325 Air Quantity

Although the Agency believes that the promulgation of paragraph (d)

of this standard was done appropriately, it is being reproposed for the

purposes of receiving and giving consideration to all pertinent

comments. Paragraph (d) would require that areas where mechanized

mining equipment is being installed or removed be ventilated and that

the quantity of air and the ventilation controls necessary to provide

these quantities be specified in the approved ventilation plan. As

demonstrated by the explosion at the William Station Mine, ventilation

of these areas is essential and will greatly enhance the protection

provided to miners.

Section 75.330 Face Ventilation Control Devices

During the informational meetings and later discussions, it became

apparent that members of the mining community were concerned about the

appropriateness of using a performance standard relative to the volume

of air that must be provided to working faces. It was suggested that

such an approach suffered from two flaws: (1) By simply requiring

sufficient air, a problem could develop and go unnoticed before

corrective action is required; and (2) since most miners do not have

the means for measuring ventilation parameters; i.e., anemometers and

methane detectors, it may not be possible for the average miner to

determine compliance with the performance standard. It has been

suggested that in addition to the performance standard, the Agency

should propose requirements for line brattice similar to those that

existed in the previous regulation. After considering this

recommendation in light of the expressed concerns, the Agency is

proposing, in paragraph (c), that when a line brattice or other face

ventilation control device is damaged to the extent that ventilation of

the working face is inadequate, production activities would cease until

necessary repairs are made. It is the intent of the Agency to assure

that damaged ventilation controls are repaired and that mining is

discontinued until adequate face ventilation is restored.

Section 75.332 Working Sections and Working Places

Although the Agency believes that the promulgation of paragraph

(a)(1) of this standard was done appropriately, it is being reproposed

for the purposes of receiving and giving consideration to all pertinent

comments. The ventilation of working areas has historically been

accomplished through the use of a separate split of intake air. The

proposal would provide this same level of protection to miners working

in areas where equipment is being installed or removed.

The Agency is not proposing any changes to Sec. 75.332 at this

time. However, questions have come to the attention of the Agency

concerning the existing standard. The following discussion is intended

to address these questions.

The existing requirements of Sec. 75.332 are largely derived from

earlier MSHA regulations (Sec. 75.311 and Sec. 75.312). Under existing

Sec. 75.332, air which has passed through any area not examined under

Sec. 75.360, Sec. 75.361 or Sec. 75.364, or through any area which has

been second mined, cannot be used to ventilate any working place. After

the rule became effective, it was suggested that it would be possible

to ventilate working places with intake air coursed through an

evaluated, nonpillared worked-out area, because evaluation in lieu of

travel to the point of deepest penetration is at some times acceptable

under Sec. 75.364. As explained in the following discussion, this is

not the case. Existing Sec. 75.332(a)(1) requires that each working

section and each area where mechanized mining equipment is being

installed or removed be ventilated by a separate split of ``intake

air.'' Existing Sec. 75.301 defines return air as ``Air that has

ventilated the last working place of any working section or any worked-

out area, whether pillared or nonpillared * * *.'' Reading these two

existing provisions together, one concludes that air that has

ventilated a worked-out area is return air and therefore cannot be used

to ventilate any working section or any area where equipment is being

installed or removed.

A second question concerns the conditions under which air that has

passed by an unsealed worked-out area can be used to ventilate a

working section. Worked-out areas that are not sealed must be

ventilated, Sec. 75.334(a). Under Sec. 75.332(b)(1) the air used to

ventilate worked-out areas cannot be used to ventilate working

sections, unless examined in accordance with Sec. 75.360, Sec. 75.361,

or Sec. 75.364. There is only one condition under which air that passes

by a worked-out area that is not examined can be used to ventilate a

working section or an area where equipment is being installed or

removed. This is when the worked-out area is ventilated by a separate

split of air and the remainder of the intake air continues past the

worked-out area. This remaining intake air could be used to ventilate a

working section or an area where equipment is being installed or

removed. However, the air that enters the worked-out area cannot

reenter the intake air course because the definition of return air, in

Sec. 75.301, states in part that ``If air mixes with air that has

ventilated the last working place on any split of any working section

or any worked-out area, whether pillared or nonpillared, it is

considered return air.'' In the case of worked-out areas with multiple

openings, this would preclude air from being used to ventilate a

working place when it enters a worked-out area in one entry and exits

the worked-out area in another entry to remix with the air passing by.

To determine that the air that has passed by a worked-out area has

not been contaminated, proposed Sec. 75.360(b)(4) would require that

when intake entries carry air by worked-out areas to ventilate working

places where persons are scheduled to work, the approaches to the

worked-out areas be preshift examined immediately inby and outby each

entry that carries air into the worked-out area. The purpose of this

examination is to assure that the air is not oxygen deficient and does

not contain methane in excess of allowable limits and to determine that

the air is not coming from the worked-out area. By preshift examining

the intake entries in these areas, it can be determined that the air in

these entries is suitable for use in working places. Additionally,

proposed Sec. 75.360(b)(4) would require that when intake entries carry

air by worked-out areas to ventilate working places where persons are

scheduled to work, the entries used to carry air into the worked-out

area be preshift examined at a point immediately inby the intersection

of each entry with the intake air course. Preshift examining of these

entries is intended to assure that air that enters a worked-out area in

one entry does not reenter the intake air course.

While the Agency is not contemplating a change to Sec. 75.332 at

this time, comments are specifically solicited on the issues discussed.

Section 75.333 Ventilation Controls

The Agency is proposing to revise paragraphs (a), (b)(1), (b)(3),

(b)(4), and (e)(1) and add new paragraph (h) to Sec. 75.333.

As proposed, paragraphs (b)(1), (b)(3), and (b)(4) would be revised

to clarify the application of the permanent ventilation control

standards when a continuous face haulage system is used. Continuous

face haulage systems employ mobile bridge conveyors to transport coal

directly from the continuous mining machine to a low profile conveyor

belt. The mobile bridge system uses a ``dolly'' to transfer the coal to

the low profile conveyor belt at the section loading point. Because the

dolly travels along the low profile conveyor belt, the location of the

section loading point changes during mining as the mobile bridge dolly

moves. For escapeway purposes, paragraph (b)(4) would designate the

loading point for a continuous haulage system as the inby most point of

travel of the dolly.

In the past, the Agency has not required the use of permanent

ventilation controls to separate continuous face haulage systems from

return, intake, or primary escapeway entries in rooms developed 600

feet or less from the centerline of the entry from which the rooms were

developed. As with the existing standard, proposed paragraph (b)(1)

would require permanent stoppings or other permanent ventilation

control devices between intake and return air courses, except temporary

controls may be used in rooms that are 600 feet or less from the

centerline of the entry from which the room was developed. The proposal

would clarify the existing standard by explicitly stating that when

continuous face haulage systems are used, temporary controls may be

used to separate the system from the return and intake in rooms

developed 600 feet or less from the centerline of the entry from which

the rooms were developed. Because the room in which the continuous

haulage system is installed is continuously attended by the system

operators, an immediate response to any safety-related problem with the

haulage system would be expected. Additionally, two or three rooms are

often concurrently developed using this system and the life of the

actively developing rooms is often less than three days. The result of

this short life is that mining in these rooms would often be completed

before construction of permanent controls is finished. The proposal

recognizes the short-lived nature of these rooms and permits the use of

properly constructed temporary controls to deliver ventilation to the

faces. Requiring the construction of permanent controls in these

instances would result in no additional safety benefit. The Agency has

also received comment that additional material handling hazards would

be associated with the transportation of permanent control construction

materials into an often limited number of rooms during development.

Additionally, access to the continuous haulage system is required

through crosscuts for maintenance and operation of the system.

For these reasons, proposed paragraph (b)(3) would also be revised

to require that when continuous face haulage systems are used,

permanent stoppings or other permanent ventilation control devices must

be built and maintained to separate the haulage entry in which the low

profile belt structure is located from intake entries only to the outby

travel point of the dolly. The proposal would also provide that for

continuous haulage systems, temporary ventilation controls may be used

in rooms that are 600 feet or less from the centerline of the entry

from which the rooms were developed. In all other cases permanent

stoppings or other permanent ventilation control devices would continue

to be required to separate belt conveyor haulageways from intake air

courses when air in the intake air course is used to provide air to

active working places.

Proposed paragraph (b)(4) would continue to require permanent

stoppings or other permanent ventilation control devices ``* * * to

separate the primary escapeway from belt and trolley haulage entries,

as required by Sec. 75.380(g).'' In addition, the proposal would

require that when continuous face haulage systems are used, the loading

point for purposes of Sec. 75.380(g) would be the inby most point of

travel of the dolly. The Agency intends that this separation be

maintained to the most inby point of travel of the dolly in order to

provide protection along the entire length of the conveyor belt entry.

A greater or lesser distance for the separation of the conveyor belt

structure from the primary escapeway may be specified and approved in

the ventilation plan provided it poses no hazard to miners. This

provision is consistent with the requirements of Sec. 75.380(g).

The portion of the structure necessary to accommodate the movement

of the dolly is considered as part of the face haulage system.

Consistent with current MSHA policy, waterlines would not be required

to parallel continuous face haulage systems using a low profile

conveyor belt if the length of the belt is less that 600 feet and

sufficient fire hose is available to extend to the working face. Fire

suppression devices and signal and alarm systems are not required to be

installed along such conveyor belts. However, the belts considered as

face equipment must have fire protection at the belt drive as required

by Sec. 75.1100-2(e) of the existing standard and, if hydraulically

operated, must have fire suppression devices as required by existing

Sec. 75.1107. Additionally, for safety reasons, check curtains should

not be installed across the area of travel of the dolly.

The Agency has become aware of questions on the part of a segment

of the industry relative to what are acceptable construction methods

and materials for the construction of permanent ventilation controls,

excluding seals, that will result in controls that satisfy the

definition of durable given in paragraph (a) of the existing standard.

The Agency is addressing these questions by proposing to eliminate the

definition of durable and to modify paragraph (e)(1) to require these

controls to be constructed in a manner and of materials that results in

a construction that has been tested and shown to have a minimum

strength of 39 pounds per square foot as tested under ASTM E72-80

Section 12--Transverse Load-Specimen Vertical, load only. The proposal

retains the intent and requirement of the existing standard because the

8-inch hollow-core concrete block stopping with mortared joints, to

which all other constructions were tied under the definition of durable

in the existing standard, has been tested and shown to have a minimum

strength of 39 pounds per square foot.

The Agency recognizes that other construction methods and materials

may be available or developed that will result in permanent ventilation

controls that are suitable for the intended purpose. The proposal would

permit alternative constructions for ventilation controls constructed

after [INSERT THE EFFECTIVE DATE OF THIS RULE] under paragraph

(e)(1)(i) provided they have been tested and shown to have a minimum

strength of 39 pounds per square foot. For a control to be acceptable,

the operator would have to demonstrate that the control has been tested

and shown to provide a strength of 39 pounds per square foot as tested

under ASTM E72-80 Section 12--Transverse Load-Specimen Vertical, load

only. In instances where a construction has already been tested and

shown to possess the requisite strength, the operator need only provide

documentation of the test results. MSHA will maintain and will make

available for review at each MSHA District Office a listing of

construction methods and materials that have been tested and have

demonstrated a strength of at least 39 pounds per square foot. Persons

wishing to have a construction method or material included in this

listing should submit documentation of testing to the Agency. To the

extent possible, MSHA will also maintain a listing of construction

methods and materials that have failed to demonstrate a strength of at

least 39 pounds per square foot when tested under ASTM E72-80 Section

12--Transverse Load-Specimen Vertical, load only. Persons wishing to

have a construction method or material included in this listing should

submit documentation of testing to the Agency. It should be noted that

solid concrete block stoppings that are dry-stacked and plastered on

only one side have not been shown to have a minimum strength of at

least 39 pounds per square foot when tested under ASTM E72-80 Section

12--Transverse Load-Specimen Vertical, load only. Unless a stronger

plaster is developed, it is unlikely that a stopping plastered on only

one side would be acceptable under the current rule or this proposed

revision.

As with the existing rule, the proposal would require, in paragraph

(e)(1)(ii), that all overcasts, undercasts, shaft partitions, permanent

stoppings, and regulators, installed after November 15, 1992, be

constructed of noncombustible material.

Also like the existing standard, the proposal lists materials that

would be suitable for these controls and would continue to prohibit

ventilation controls installed after November 15, 1992, from being

constructed of aluminum.

The Agency is proposing a new paragraph (h) to assure that all

permanent ventilation controls, including all doors and seals,

regardless of the construction date, be maintained to serve the purpose

for which they were built. Existing Sec. 75.333(e)(1) requires that

ventilation controls be maintained to serve the purpose for which they

were built. Because existing Sec. 75.333(e)(1) also specifies that

ventilation controls installed after November 15, 1992, be constructed

of durable and noncombustible material, a commenter questioned whether

the maintenance requirement applied only to ventilation controls

constructed after November 15, 1992. That is not the case. Given the

importance of these devices in preserving the integrity of the mine

ventilation system, MSHA is proposing the maintenance provision in a

new paragraph to explicitly state that all permanent ventilation

controls, including seals, must be maintained to serve their intended

purpose. With regard to seal maintenance, the Agency does not intend

that the maintenance standard would be applied to seals located within

another sealed area. Further, the Agency does not intend that the

standard would apply to seals which have become consumed within a gob

area which is ventilated and evaluated in a manner approved through the

mine ventilation plan.

Section 75.334 Worked-out Areas and Areas Where Pillars Are Being

Recovered

MSHA is proposing to revise paragraph (e) and to repropose existing

paragraph (f). A requirement would be added in paragraph (e) that

provides that in addition to designing mining systems so that worked-

out areas can be sealed, the location and sequence of construction of

proposed seals would also be specified in the approved ventilation

plan. Improper location and sequencing of seal construction can have a

deleterious effect on mine air quality and ventilation and therefore

the location and sequence of construction of these seals should be

reviewed and approved as a part of the ventilation plan. Under the

previous standard, the proposed location and sequence of construction

of all necessary mine seals was required to be submitted for approval

as part of the sealing plan required by Sec. 75.330. Under the existing

standard, the location of proposed seals is required to be shown on the

ventilation map required by Sec. 75.372. Showing the location on the

map does not subject the location to approval and therefore the Agency

agrees that it does not satisfy the objective of assuring proper

location and sequencing. The proposal would rectify this situation.

Through meetings with various segments of the mining community, the

Agency also became aware of a concern that paragraph (f) of Sec. 75.334

may have been promulgated without the benefit of adequate comment.

Paragraph (f) addresses mines with a demonstrated history of

spontaneous combustion or those located in coal seams determined to be

susceptible to spontaneous combustion. Although the Agency believes

that the promulgation of paragraph (f) of this standard was done

appropriately, it is being reproposed for the purposes of receiving and

giving consideration to all pertinent comments.

As discussed in the preamble to the existing standard, several

commenters suggested that bleeder systems should not be required for

all mines, stating that in some mines the practice of ventilating

worked-out areas increases the risk of spontaneous combustion by

supplying oxygen to combustion-prone materials in these areas. These

commenters requested that the final rule include provisions to address

spontaneous combustion. MSHA recognized the need to reduce the flow of

oxygen to areas where there is a likelihood of spontaneous combustion

and the existing rule requires the approved ventilation plan to address

spontaneous combustion in mines with a demonstrated history of this

hazard or mines that are located in coal seams determined to be

susceptible to spontaneous combustion.

Experience gained through application of this standard has

demonstrated that paragraph (f) applies to only a few mines. However,

studies by the Bureau of Mines have identified the volatile properties

of coal seams and have determined that certain seams are susceptible to

spontaneous combustion. The existing standard, as reproposed, is also

directed to mines in these seams.

Under paragraph (f) of the proposal, the approved ventilation plans

for mines that are susceptible to spontaneous combustion must specify

measures to detect methane, carbon monoxide, and oxygen concentrations

in worked-out areas. These measures must be taken during and after

pillar recovery and in worked-out areas where no pillars have been

recovered. The purpose of these measures is to determine if worked-out

areas must be ventilated or sealed. If the methane concentration or

other hazards in the worked-out area cannot be controlled while the

mine is limiting airflow to avoid spontaneous combustion, it may be

necessary to ventilate or seal the worked-out area. These measures also

help to determine the extent to which the worked-out areas can be

ventilated without increasing the spontaneous combustion hazard.

The Agency is concerned with the inability of some mines that have

a spontaneous combustion problem to reduce the oxygen content to a

sufficiently low level. It is well known that the oxygen level in a gob

varies depending on the location where the measurement is made. For

example, the periphery of a gob normally will have higher oxygen levels

than the interior of the gob. The oxygen level in the interior of the

gob is critical when dealing with spontaneous combustion. If conditions

are such that the oxygen content in critical areas within a gob cannot

be reduced below that necessary for a methane ignition to occur, a

bleederless system may not be appropriate. The Agency solicits comments

on this subject.

Under the provisions of paragraph (f) the operator is required to

specify the action that will be taken to protect miners from the

hazards of spontaneous combustion. This requirement would be triggered

if the mine has a demonstrated history of spontaneous combustion, or,

if an evaluation of the susceptibility of the coal seam to spontaneous

combustion leads to a mine operator determination that a bleeder system

should not be used. In these cases the approved ventilation plan must

specify the methods that the operator will use to control spontaneous

combustion, as well as accumulations of methane-air mixtures and other

gases, dusts, and fumes in the worked-out area.

During informational meetings and through the application of this

standard, the Agency has become aware that the conditions under which

air flow can be adjusted within a bleeder system is the subject of some

concern. The following discussion is intended to address this concern

and clarify the Agency's position. When adjustments to air flow in the

bleeder entries are needed to assure proper functioning of the system,

these adjustments would be made in accordance with Sec. 75.324,

Intentional changes in the ventilation system. As explained in the

preamble discussion of existing Sec. 75.324, when the adjustment in the

bleeder system results in a change in direction of the air in the

bleeder entry, this is a change in ventilation that could materially

affect the safety or health of miners, and the precautions of

Sec. 75.324 apply. As addressed under Sec. 75.324, other changes to air

flow in the bleeder entry may also materially affect the safety or

health of miners, and the precautions of Sec. 75.324 would apply.

However, it is not intended that each and every change to bleeder

ventilation be considered to materially affect the safety or health of

miners. For example, minor changes needed to correct a localized

condition, such as removing a methane accumulation in a high spot, may

be possible. The operator must evaluate each change prior to its

implementation and, if doubt exists as to whether the change is

material, safety dictates that the change be treated as a material

change and the provisions of Sec. 75.324 be followed.

Section 75.340 Underground Electrical Installations

MSHA proposes to revise paragraph (a) of existing Sec. 75.340 for

the purpose of clarifying the standard and to add requirements that a

visual and audible alarm be provided on installations utilizing

automatically activated doors and that, for installations equipped with

sensors, monitoring of intake air ventilating battery charging stations

be done with sensors not affected by hydrogen. For clarity,

requirements for underground electrical installations to be in either

noncombustible structures or areas or to have fire suppression systems

have been put into separate paragraphs. Paragraph (a)(1) sets out the

requirements that apply when a noncombustible structure or area is used

for underground electrical installations. Similarly, paragraph (a)(2)

sets out the requirements that apply when a fire suppression system is

used. A provision has been added to proposed paragraph (a)(1)(iii) that

requires that electrical installations be equipped with a device to

activate a visual and audible alarm located outside of the enclosure on

the intake side of the installation. In addition, to maintain

consistency with proposed paragraphs (a)(1)(ii) and (a)(2)(ii) of this

section, proposed paragraph (a)(1)(iii) would be revised to include the

provision that monitoring of intake air ventilating battery charging

stations be done with sensors not affected by hydrogen. Proposed

paragraph (a)(1)(iii) addresses installations which are ventilated with

intake air and equipped with sensors to monitor for heat and for carbon

monoxide or smoke for the purpose of activating and automatically

closing doors. The device would activate when the temperature reaches

165 degrees Fahrenheit or the carbon monoxide concentration reaches 10

parts per million above the ambient level for the area, or the optical

density of smoke reaches 0.05 per meter. The visual and audible alarm

required should be situated so that it can be seen or heard by persons

traveling in the intake entry immediately adjacent to the installation.

It was suggested to the Agency that these electrical installations may

be susceptible to fire and the fire could go undetected. The visual and

audible alarms would provide additional safety at these installations.

Section 75.342 Methane Monitors

Informational meetings, later discussions on the rule, and recent

experience have indicated that simply requiring methane monitors to be

maintained in permissible condition does not completely satisfy the

need for assuring proper maintenance. It was suggested that it is

necessary to have a requirement that a trained person perform

maintenance to preclude the possibility that a person with less than

the necessary understanding of the monitor and the permissibility

requirements would be assigned the task. Under the proposal, methane

monitors must be properly maintained at all times. Like the existing

rule, proposed paragraph (a)(4) would require that each methane monitor

be calibrated with a known air-methane mixture at least every 31 days.

The Agency would expect that, when necessary to maintain

permissibility, methane monitors would be calibrated more frequently.

To assure the appropriate level of maintenance, paragraph (a)(4)(i)

would require that this maintenance be done by a trained person. To

further assure the adequacy of the maintenance provided, paragraph

(a)(4)(ii) would require, similar to the previous standard, the

operator to develop and adopt a written maintenance program, a copy of

which would be made available for review by authorized representatives

of the Secretary and the representative of miners. The investigation

into the recent explosion at the No. 3 Mine, Southmountain Coal

Company, Inc., illustrates the importance of proper maintenance of

methane monitors and the need for assuring that maintenance and

calibration are being done properly. Although the Southmountain

investigation report did not conclude that the methane monitor on the

continuous mining machine was involved in the explosion, it did state

that, ``* * * the methane monitor was likely in a condition that would

not have allowed for accurate atmospheric monitoring of the area prior

to and at the time of the explosion * * *.'' Appendix H of the report

states, ``The methane monitor was not maintained as approved due to the

use of a rag in place of the sintered metal screen filter in the dust

guard. The methane monitor was not properly calibrated, as received. If

this condition existed at the time of the explosion, the methane

monitor would not have been able to accurately detect the presence of

methane.'' The Agency believes that the best way to assure that

maintenance and calibration are properly done is through a written

maintenance program with which everyone involved is familiar.

The Agency would expect that, at a minimum, the maintenance program

would include the following: (1) Checks to assure that all components

of the methane monitor are securely attached to the machine on which it

is mounted and that all packing glands are properly packed and secured;

(2) Checks to assure that the sensor head is installed as close to the

face end of the machine as practicable and that the vent holes and

filter(s) on the sensor head are not clogged with water, dust, or other

material; and (3) Checks to assure that the warning device can be seen

or heard by the machine operator at all locations from which the

machine is operated and that the lens(es) protecting the meter and

indicating lamps is not cracked or broken. The maintenance program

should also make provisions to assure that the methane monitor meter or

readout assembly is properly adjusted to indicate zero percent methane

when no methane is present and that it is not possible to defeat the

monitor by holding or blocking the machine's reset switch in the start

position. The program should also specify the procedure for assuring

that a warning is given when 1 percent methane is indicated on the

meter or readout assembly and that all motors and lights on the machine

are automatically deenergized when 2 percent methane is indicated on

the meter or readout assembly.

During informational meetings and subsequent discussions, MSHA

heard suggestions that without a requirement for a record to be

maintained of calibration tests, similar to that required by the

previous regulation, there would be no way for the Agency or miners to

verify that the tests were made. Upon reconsideration, and in light of

the Southmountain explosion investigation, MSHA agrees that records of

calibration tests would be beneficial and is therefore proposing, in

paragraph (a)(4)(iii), that a record of all calibration tests be kept

in a book maintained for this purpose on the surface at the mine. Like

other records required by this proposal, the records of methane monitor

calibration tests are to be made in a state-approved book or in a bound

book with sequential machine-numbered pages. This is being proposed to

reduce the likelihood that pages or records could be lost or misplaced.

Comments are solicited on the use of this type of recordkeeping book

and on an alternative approach wherein the Agency would develop, in

coordination with the states, books specific for the required records.

Under paragraph (a)(4)(iv) of the proposal, the records would be

required to be retained for at least 1 year at a surface location at

the mine and be made available for inspection by representative of

miners and by authorized representatives of the Secretary.

Section 75.344 Compressors

This standard specifies requirements for compressors in underground

coal mines. The proposal would revise paragraph (a)(1), redesignate

existing (b)(2) as (b)(3) and add new (b)(2) and (e).

Improperly used or maintained compressors can present a significant

risk of fire. To minimize this hazard to miners, the existing

regulation addresses the detection and suppression of compressor fires,

and specifies installation and operation requirements for compressors.

The Agency has stayed paragraph (a)(1) of Sec. 75.344 of the existing

regulation, which requires all compressors to be located in

noncombustible structures or areas. During the informational meetings,

it was brought to MSHA's attention that in some instances requiring

such a structure could present a fire hazard.

The proposal recognizes in paragraph (a)(1) that it is possible to

provide the desired level of protection by permitting compressors to be

operated while attended, rather than requiring that they be located in

noncombustible structures or areas. Commenters pointed out that

requiring all compressors, including portable compressors, to be

located in noncombustible structures or areas might result in a fire

hazard. The primary hazard identified in these instances is the buildup

of heat within the structure if sufficient ventilation for cooling is

not provided. Another hazard identified during discussions on this

section is potential delay in roof bolting during construction of a

suitable structure or area for the compressor used for bolting.

Recognizing these potential hazards, the proposal would require

compressors to be located in noncombustible structures or areas,

provided adequate ventilation is maintained for cooling or, as an

alternative, would require compressors to operate while attended. If

the compressor is operated while attended, it is the Agency's intention

that the person be able to see the compressor and recognize a problem

and is close enough to activate the required fire suppression system

and assure that the compressor is deenergized or shut off. This would

not preclude the individual from performing other duties, including

those involving the use of the compressor. However, it would require

that the individual be in close proximity to the compressor. The Agency

solicits comments on whether the standard should specify a distance and

what that appropriate distance would be. If a specific distance is

recommended, the commenters should also provide the rationale for that

distance.

Regardless of whether the compressor is located in a noncombustible

structure or area or operated while attended, existing paragraph (b)(1)

requires that the compressor, if not ventilated with air coursed

directly into a return air course or to the surface, be operated only

while it can be seen by a person designated by the operator. The

difference between proposed paragraph (a)(1), and the existing

paragraph (b)(1) would be the distance the designated person could be

from the compressor. Under proposed paragraph (a)(1) the designated

person would be required to be close enough to activate the fire

suppression system, to deenergize or shut off the compressor, and to

see the compressor. Under paragraph (b)(1), the designated person need

only be able to see the compressor.

In response to comments, the Agency is proposing paragraph (b)(2),

which provides additional flexibility for compressor installations

while maintaining the same level of protection. Proposed paragraph

(b)(2) would add an alternative that would apply to compressors located

immediately adjacent to a return air course where a substantial

pressure differential exists. This alternative would not be appropriate

for applications near working sections where low ventilation pressure

differentials exist.

Substantial pressure differentials are necessary to provide the air

velocities required to prevent smoke rollback.

Under proposed (b)(2), a compressor could be situated adjacent to a

return air course, between two permanent ventilation controls through

which an air split would be maintained from a small diameter opening in

the intake-side control to a larger diameter opening in the return-side

control. In lieu of the intake-side ventilation control, a door may be

constructed in accordance with Sec. 75.333 (d)(1) and (d)(2). Section

75.333(d)(3), which requires doors to be constructed in pairs, would

not apply in this case. The Agency intends that this door remain closed

at all times while the compressor is operating. This door would provide

easy access to the compressor. The Agency would continue the practice

of accepting as doors the fire-resistant check curtains described by

Steven J. Luzik in ``MSHA Develops New Fire-Resistant Check Curtains,''

Coal magazine, pages 102-104, June 1993. The ventilating air quantity

must be adequate to provide the essential cooling of the compressor.

The Agency expects operators to provide the air quantity necessary to

assure that the maximum ambient operating temperature specified by the

compressor's manufacturer is not exceeded. Similarly, any other

ventilating or temperature parameters specified by the manufacturer

would be considered in determining an adequate ventilating air

quantity.

In addition to an air quantity necessary to provide cooling, the

air velocity through the intake-side opening would be required to be

sufficient to prevent any air reversal or possible smoke rollback in

the event of a compressor fire. In determining sufficient air

velocities, the Agency has placed in the rulemaking record the 1977

MESA Informational Report, Ventilation to Control the Smoke From a

Fireproof Structure, (IR 1054). That report concludes that smoke

rollback should not occur if the centerline velocity through the

intake-side opening (not to exceed 16 x 24 inches) is at least 1,100

feet per minute (fpm) and the discharge opening is not smaller than the

intake opening with at least 10 feet between the ventilation controls.

The report also indicates that the intake opening should be close to

the floor and the discharge opening should be near the roof. The Agency

solicits comments on whether the velocity and associated parameters

outlined in IR 1054 are appropriate.

The proposed paragraph (b)(2) alternative also requires sensors for

heat or carbon monoxide or smoke to be installed between the two

permanent ventilation controls. The sensors would be required to

activate a visual and audible alarm located outside of the enclosure on

the intake side when either condition specified in paragraph (b)(3) (i)

or (ii) occurs. The visual alarm should be situated so that it can be

seen by persons traveling in the intake entry immediately adjacent to

the enclosure.

Paragraph (e) of the proposal has been added in response to

suggestions that compressors have an automatic shutdown feature that

deenergizes or shuts off the compressor when the required fire

suppression system is activated. The Agency recognizes that under

Sec. 75.1107-4 automatic deenergization is required if the automatic

fire suppression system is activated on unattended electrically powered

compressors. However, paragraph (e) would clarify that automatic

deenergization or shutdown is required for both attended and unattended

electric and diesel powered compressors. This paragraph also would

require the compressor to be automatically deenergized or shut off if

one or more of the doors (required by paragraph (b)(3)) close.

Historically, fires on compressors that continue to operate have

resulted in oil being released, which has contributed to the severity

of the fire. For this reason, the Agency believes that safety is best

served by requiring compressors to be automatically deenergized or shut

off when the fire suppression system is activated.

It was suggested that the cutoff for application of Sec. 75.344 be

changed from 5 horsepower for all compressors to 30 horsepower for

reciprocating compressors and 5 horsepower for all other types of

compressors. The rationale presented for this suggestion is that

reciprocating compressors of up to 30 horsepower contain about the same

amount of lubricating oil as a 5 horsepower oil-flooded rotary

compressor. This suggestion is not adopted in the proposal because the

Agency has information (Report No. 06-292-87 of the Industrial Safety

Division, Pittsburgh Safety and Health Technology Center) that the

predominant hazard for fire or explosion in reciprocating compressors

is not the lubricating oil but rather the formation of carbonaceous

deposits in the discharge system. A review of accident reports

indicated that nine mine fires started in compressors between 1970 and

1992. Two of these nine fires occurred in compressors of the type

subject to a buildup of carbonaceous deposits. Although it is not known

that this buildup was the cause of these fires and the compressors

involved were larger than 30 HP, these fires are of concern to the

Agency. The Agency solicits additional comments on the safety

considerations associated with reciprocating compressors.

Section 75.360 Preshift Examination

MSHA is proposing several modifications to the requirements in the

existing Sec. 75.360, Preshift examinations. Paragraph (e) would be

removed, existing paragraphs (f) through (h) would be redesignated as

(e) through (g), paragraphs (a), (b), (c), and (f) would be revised,

and new paragraphs (b)(8) through (b)(10) would be added.

The informational meetings and later discussions on the rule

indicated some confusion over the application of preshift examination

requirements to pumpers. The questions focused on the need to preshift

examined areas of the mine where pumpers were scheduled to work or

travel. In response to these questions, the Agency has reviewed its

position on this issue and has determined that the interest of safety

is best served by permitting pumpers to perform examinations for

themselves, provided they are certified. The existing regulation

requires that areas where pumpers are assigned to work or travel be

preshift examined even if the pumper is certified. The proposal would

modify Sec. 75.360 by requiring in proposed paragraphs (a)(1) and

(a)(2) that certified pumpers perform these examinations if the area

has not been preshift examined. However, if the pumper is not

certified, the proposal would continue to require the areas where the

pumper is assigned to work or travel to be preshift examined. Paragraph

(a)(2) of the proposal would require that the pumper make a record by

or at the end of the shift of all hazardous conditions found.

As with other examinations required by this subpart, no one may

accompany the pumper during this examination. If persons other than the

certified pumper are scheduled to enter the area, a preshift

examination is required. However, pumpers may conduct supplemental

examinations in accordance with Sec. 75.361 for other persons, provided

certified pumpers: (1) have been designated by the operator to conduct

these examinations; (2) conduct these examinations within 3 hours prior

to anyone's entering the area; and (3) conduct these examinations in

areas where persons were not scheduled to work prior to the beginning

of the preshift examination. The proposal would provide at least the

same level of safety as the existing regulation because a complete

examination by a certified person would still be required and the

examination would be conducted closer to the time that miners would

actually enter the area.

Paragraph (b) is proposed for revision to address conditions to be

checked by the preshift examiner. Under the existing rule, the preshift

examiner is required to examine for hazardous conditions. The preamble

to the existing rule states the Agency's position that ``Most `hazards'

are violations of mandatory standards.'' (57 FR 20894, May 15, 1992.)

It further states that requiring a preshift examiner to look for all

violations could distract the examiner from the more important aspects

of the examination and that a district manager could require the

preshift examiner to include examination for other hazards. Upon

reconsideration, the Agency is proposing that the preshift examination

be expanded to include an examination for noncompliance with mandatory

safety or health standards that could result in a hazardous condition,

as well as other hazardous conditions. This proposal places the

examiner and the operator in a proactive rather than a reactive role

and therefore has the potential to enhance safety by identifying a

condition before a hazard exists.

Under proposed paragraph (b)(1), roadways, travelways and track

haulageways where persons are scheduled to work or travel during the

oncoming shift must be preshift examined. The proposal would clarify

that the preshift examination includes travelways in addition to

roadways and track haulageways. This is being proposed based on

comments received that the terms ``roadways'' and ``track haulageways''

specifically refer to areas where mobile powered equipment is operated.

The addition of the term travelways in the proposal would require areas

where persons are scheduled to travel on foot to also be preshift

examined since hazards may also exist in these areas. The remaining

portion of the existing paragraph has been transferred to paragraph

(b)(10).

Proposed paragraph (b)(3) would require an examination for

hazardous conditions and noncompliance with mandatory safety or health

standards that could result in a hazardous condition, tests for oxygen

deficiency and methane, and a determination if the air is moving in its

proper direction on any section that is not scheduled to operate but is

capable of producing coal by simply energizing equipment. This is in

addition to the existing requirement that these examinations and tests

be made on working sections and areas where mechanized mining equipment

is being installed or removed. It has been the Agency's position that

sections that are capable of producing coal by simply energizing

equipment should be examined in accordance with Sec. 75.361,

Supplemental examinations. However, as pointed out by commenters, a

number of fatalities have been the result of persons being sent into

areas that should have been examined but were not. Because there is a

reasonable likelihood that miners will at some point during a working

shift enter sections that are set up to mine coal, the Agency is

proposing that these sections be preshift examined.

The Agency has become aware of an opinion of a segment of the

mining community that those parts of Sec. 75.360 related to areas where

mechanized mining equipment is being installed or removed were

promulgated without the benefit of adequate comment. Although the

Agency believes that the promulgation of this standard was done

appropriately, it is being reproposed for the purposes of receiving and

giving consideration to all pertinent comments.

As stated in the preamble to the existing rule, ``The Agency has

always considered these areas to be subject to the requirements of the

preshift examination; however, an investigation following an explosion

at the William Station Mine indicated that some confusion existed on

this issue.'' (57 FR 20894, May 15, 1992.) The Agency's position on

this issue remains unchanged at this time; however, comments are

specifically solicited relative to the need to preshift examine these

areas.

Paragraph (b)(3) would also require the examination to include a

test of the roof, face and rib conditions on these sections or in these

areas. This is to clarify the Agency's position that failures of the

roof, face and rib pose a hazard to miners. It has been suggested to

the Agency that specifically requiring this examination is proactive

rather than reactive and is therefore the preferred approach. The

Agency has reconsidered its approach and agrees.

Existing paragraph (b)(4) requires that a preshift examination of

the approaches to worked-out areas along intake air courses be

conducted if intake air passes by the worked-out area to ventilate

working sections where anyone is scheduled to work during the oncoming

shift. The proposal would revise paragraph (b)(4) by also requiring

that the entries used to carry air into these worked-out areas be

preshift examined. Under the provisions of existing Sec. 75.332(a)(1),

air that ventilates a working section or an area where mechanized

mining equipment is being installed or removed must be a separate split

of intake air. Air that ventilates a worked-out area is return air and

cannot be used. The preshift examination required by proposed paragraph

(b)(4) is intended to assure that miners are not exposed to the hazards

associated with ventilating working sections with return air and that

air that enters a worked-out area in one entry does not reenter the

intake air course. Additionally, the proposal would clarify the

Agency's intent that the examination of the approaches to these worked-

out areas be made immediately inby and outby each entry used to carry

air into the worked-out area.

Paragraph (b)(6) of the proposal addresses concerns raised during

the informational meetings and later discussions on the rule that

requiring examination or rehabilitation of rooms and entries described

in paragraphs (i) and (ii) could constitute a hazard. The existing

standard requires a preshift examination of entries and rooms driven

more than 20 feet off an intake air course without a crosscut or more

than 2 crosscuts off an intake air course without permanent ventilation

controls where intake air passes through or by these entries or rooms

to a working section where anyone is scheduled to work during the

oncoming shift. It was pointed out that often these rooms and entries

have existed without incident for many years, which has allowed methane

to bleed off. The Agency also heard assertions that as written the

existing regulation may cause a diminution of safety to miners. It was

stated that certain areas have been timbered heavily and cribbed

because of adverse roof conditions and that rehabilitating such areas

would unnecessarily expose workers removing or repositioning cribs to

hazards. It was also stated that these areas are subject to roof falls

and may remain prone to roof falls and hazardous conditions even after

rehabilitation. Finally, it was stated that any advantages that come

from physical inspection of these entries or rooms are outweighed by

the danger to which the examiner may be exposed.

In light of these concerns, the Agency has proposed that rooms and

entries developed prior to November 15, 1992, need not be preshift

examined and requests additional comment as to the impact on safety.

Proposed paragraph (b)(6) requires that entries and rooms developed

after November 15, 1992, either be preshift examined or ventilated

using permanent ventilation controls.

In response to comments, the Agency is proposing in paragraph

(b)(8) that the preshift examiner check high spots along intake air

courses where methane is likely to accumulate if equipment may be

operated in the air course during the shift. It has long been

recognized by the industry that methane can accumulate in high areas

with no indication in the normal mine entry. As equipment passes under

these areas, the methane is pulled down and mixed with the air in the

entry and may be ignited by the equipment. Through proper ventilation

and examination, this hazard can be eliminated.

During informational meetings, commenters expressed concern about

the potential fire and ignition hazards associated with electrical

installations and compressors. Paragraph (b)(9) of the proposed rule

would require that electrical installations referred to in

Sec. 75.340(a), except for water pumps, and the areas where compressors

subject to Sec. 75.344 are located, be preshift examined if the

installation or compressor is or will be energized during the shift.

Pumps would be exempted because of the limited hazard presented by

pumps and because certified pumpers would conduct examinations for

themselves in accordance with paragraph (a)(2) as they entered the area

where the pump is located. The purpose of examining electrical

installations and compressors would be to assure that methane in

unacceptable concentrations is not present in these areas and that

there are no signs of fire. The Agency solicits comments on this

proposed requirement.

In addition, the proposed rule would modify existing Sec. 75.360 to

more clearly address those situations where miners are scheduled to

work or travel after the preshift examination has begun. The proposal

would amend paragraph (a), add a new paragraph (b)(10), and make a

conforming editorial change to existing Sec. 75.360(b)(1). The existing

Sec. 75.360(b)(1) requires that a preshift examination include areas

where miners are scheduled to work or travel during the oncoming shift.

The proposal reflects the fact that on occasion miners may be given

their work assignments, and thus be scheduled to work or travel in an

area, after the preshift examination has begun. This may occur, for

example, due to changing conditions in the mine. In these cases the

supplemental examination, rather than the preshift examination, would

be required. In accordance with provisions of Sec. 75.361, a certified

person must perform an examination of any area where a preshift

examination was not made before any person enters the area. To permit

these areas to be examined other than on the preshift examination

maintains the existing level of safety because a complete examination

by a certified person would be required. The examination would be

conducted closer to the time that persons will actually enter the area,

and any area where a hazardous condition exists will be posted.

Consistent with the proposed change to paragraph (b)(3) requiring a

preshift examination on any section that is not scheduled to operate

but is capable of producing coal by simply energizing equipment,

proposed paragraph (c) would require the preshift examination to

include air measurements in these areas. Adequate ventilation is the

primary means for assuring that methane does not accumulate in these

areas, and therefore it is necessary to determine that an adequate

volume of air is present. As stated previously, because there is a

reasonable likelihood that miners will enter sections that are set up

to mine coal at some point during a working shift, the Agency is

proposing that these sections be preshift examined and that this

examination include the air measurements described in proposed

paragraph (c).

Requirements for the posting of hazardous conditions found during

the preshift examination are specified in existing paragraph (e) of

Sec. 75.360. They would be transferred to Sec. 75.363. Additionally,

under the requirements of proposed Sec. 75.363(a), hazardous conditions

found by the preshift examiner or the pumper would have to be corrected

immediately. Also, if these conditions create an imminent danger,

everyone except those persons referred to in section 104(c) of The

Federal Mine Safety and Health Act of 1977 (the Act) must be withdrawn

from the area affected to a safe area until the hazardous condition is

corrected. Only persons designated by the operator to correct or

evaluate the conditions would be permitted to enter the posted area.

The requirement that the hazardous condition be corrected immediately

is not intended to require correction by the preshift examiner. To do

so would delay the completion of the preshift examination. Rather, it

is intended that the condition be corrected immediately following its

reporting by the preshift examiner. Under the proposal the area would

be posted and would remain posted until the hazardous condition is

corrected.

The existing paragraph (g) that addresses the record that must be

made of the preshift examination would be redesignated as paragraph

(f). Commenters felt that the requirement left no latitude for

recording findings of the examiner other than those listed. The

preamble to the existing rule states that the reason for revising

recordkeeping requirements was to ``* * * lessen paperwork burden

without lessening the protection provided miners.'' This has not

changed. However, commenters indicated that by not permitting examiners

to record the results of their examinations, the protection afforded

miners could be lessened. In response to these comments, the Agency is

proposing to modify existing paragraph (g) by reinstating a previous

requirement that examiners record the results of the examination. This

would include hazardous conditions and their locations and the results

and locations of air and methane measurements. This is intended to

require the preshift examiner to record noncompliance with mandatory

standards that could result in a hazard and observations made during

the examination, such as changes in water levels, which, if left

unattended, could block ventilation, resulting in a hazard to miners.

The proposal would also clarify that the examiner must record the

results of methane tests in terms of the percentage of methane found,

as opposed to being characterized by terms such as ``trace.'' Recording

a percentage would provide more precise information for the reviewing

officials. The Agency solicits comments on this approach to recording

the results of preshift examinations.

Additionally, proposed paragraph (f) would require that a record be

made of the action taken to correct hazardous conditions found during

the preshift examination. Knowledge by mine management of the action

necessary to correct a hazardous condition is important for the proper

evaluation of the effectiveness of various actions. For example, if a

hazardous condition occurs repeatedly and the action taken to correct

it is the same each time, management should consider the effectiveness

of the corrective action being taken. This requirement is consistent

with recordkeeping requirements found in Sec. 75.363 and Sec. 75.364.

Following publication of the final ventilation rule in May 1992,

comments received by the Agency indicated that a change was perceived

in the requirement for ``prompt'' countersigning by the mine foreman

or, in the absence of the mine foreman, by the person designated to

perform the duties of the mine foreman. The final rule did not include

the previous requirement that the mine foreman must countersign the

report ``promptly.'' Although no change was intended by the Agency,

MSHA is proposing in paragraph (f) that the preshift examination report

be countersigned by the mine foreman by the end of the mine foreman's

next scheduled working shift. The Agency intends that the mine foreman,

the person most responsible for the day-to-day operation of the mine,

be notified of the information contained in the reports. Allowing until

the end of the mine foreman's next regularly scheduled working shift to

countersign the report would assure that the mine foreman is aware of

the results of all preshift examinations and can implement necessary

corrective actions in a timely manner.

The proposal would also require that within two scheduled

production days after the mine foreman has countersigned, the record of

the examination be countersigned by the mine superintendent, mine

manager, or other mine official to whom the mine foreman is directly

accountable. This would be similar to the requirement of the previous

regulation that the superintendent countersign records of the preshift

examination. The preamble to the existing standard discusses removing

the countersigning requirement by the superintendent on the basis that

the superintendent, in many cases, is not a certified person and the

mine foreman is given responsibility for countersigning because the

mine foreman is the person most knowledgeable of the day-to-day

operation of the mine. Countersigning by the mine foreman was retained.

However, as indicated during informational meetings and subsequent

discussion, the mine foreman is not necessarily the person in a

position to redirect resources to address the safety concern. After

reconsidering the existing language, the Agency is proposing to require

countersigning by the mine foreman and by the superintendent, mine

manager, or other official to whom the mine foreman is accountable, to

assure that a higher level official, empowered to redirect resources,

is aware of any condition requiring corrective actions. Since this

second level official may not be physically located at the mine on a

full-time basis, a period of two scheduled production days is proposed

as a reasonable period of time for countersigning. The Agency solicits

comments on this approach to countersigning the report of the preshift

examination.

The proposal would require that the record be made in a state-

approved book or in a bound book with sequential machine-numbered

pages. Comments are solicited on this approach and on an alternative

approach wherein the Agency would develop, in coordination with the

states, books specific for the required records.

Identical provisions to those proposed in paragraph (f) of

Sec. 75.360 for countersigning records and for keeping the records in a

state-approved book or in a bound book with sequential machine-numbered

pages appear in Sec. 75.363(c) and Sec. 75.364(h).

Section 75.362 On-shift Examination

MSHA is proposing to redesignate existing (d)(1)(i) and (ii) as

(d)(1)(ii) and (iii), revise paragraphs (a)(1), (c)(1), (d)(1)(iii) and

(d)(2), remove paragraph (a)(2), and add new paragraph (a)(2) and

(d)(1)(i). MSHA also proposes to transfer the paragraphs (g) and (h)

recordkeeping and retention requirements to Sec. 75.363, Hazardous

conditions, posting, correcting, and recording, and add a new paragraph

(g).

Paragraph (a) would be modified in paragraph (a)(1) to require a

certified person to conduct an on-shift examination of a section during

any shift when anyone is assigned to work on the section and where

mechanized mining equipment is being installed or removed. The existing

rule requires that an on-shift examination be performed only on

sections where coal is produced and where mechanized mining equipment

is being installed or removed. The Agency agrees with comments received

during informational meetings that many of the same hazards can exist

for persons working on a section, regardless of whether coal is being

produced. For example, many times miners are assigned to perform

maintenance work on a section when no production is scheduled. This

maintenance work can involve disabled equipment that cannot be moved

from the face area or from an area near a pillar line. In these

situations, hazards can be equivalent to those encountered by miners

during normal coal-producing operations or similar operations on the

section.

The Agency proposes to revise paragraph (a) to incorporate the word

``on-shift'' in the first sentence of the paragraph. The word ``on-

shift'' was inserted for clarification and consistency with other

paragraphs of Sec. 75.362. The Agency is also proposing to revise

paragraph (a)(1) to clarify that sufficient on-shift examinations be

conducted to assure safety. It was suggested to the Agency that MSHA

should include language to require more than one examination if

necessary for safety, as provided for in the previous standard. The

Agency is adopting this approach and is proposing that at least once

during each shift, or more often if necessary for safety, a certified

person designated by the operator would be required to conduct an on-

shift examination of each section where anyone is assigned to work

during the shift and any area where mechanized mining equipment is

being installed or removed during the shift.

The Agency has become aware of an opinion of a segment of the

mining community that language in paragraphs (a)(1), (c)(1) and (c)(2)

requiring an on-shift examination of areas where mechanized mining

equipment is being installed or removed was promulgated without the

benefit of adequate comment. Although the Agency believes that the

promulgation of this standard was done appropriately, these paragraphs

are being reproposed for the purposes of receiving and giving

consideration to all pertinent comments. The word ``working'' is

removed from (c)(1) to assure the application of the standard would

extend to all sections.

The Agency has determined that a specific examination requirement

should be added to assure compliance with the respirable dust control

parameters designated in the mine ventilation plan. Assuring full

compliance with these parameters is important in safeguarding the

health of the miners. Agency experience shows that needed attention has

not always been given to the required respirable dust control

parameters. Citations issued by the Agency during a special spot

inspection program, undertaken in 1991 at the request of MSHA's Coal

Mine Respirable Dust Task Group, in which Agency inspectors conducted

several checks of the dust control parameters during the course of each

sampling shift, revealed that 21 percent of the 781 mining units

sampled were not complying with one or more of the parameters. In its

1992 report, the Agency's Task Group recommended that MSHA ``* * *

require coal mine operators to make periodic on-shift examinations to

verify that the ventilation plan parameters are in place and

functioning as intended'' (p. 47). The Agency agrees and considers on-

shift examinations of dust control parameters an important part of

reasonable and prudent dust control strategy.

Thus the proposal, in paragraph (a)(2), would add a new on-shift

examination requirement to address respirable dust control. Under the

proposal, at or near the beginning of any shift before coal production

begins on a section, a certified person designated by the operator

would conduct an examination for compliance with the dust control

parameters established in the mine ventilation plan. Corrective actions

to assure compliance would be required to begin immediately. The

proposed examination would include measurements for compliance with

required water pressures and flow rates, number and orientation of

water sprays, air quantities and velocities, section ventilation setup

and control device placement, and any other dust control parameter

required in the ventilation plan.

Several methods of measuring water spray pressures would be

acceptable. For example, water flow and pressure can be monitored

through the installation of an in-line water meter and a pressure

transducer. Water pressure can also be measured by permanently

installing a pressure gauge on a machine. Operators would determine the

working relationship between the pressure gauge reading and the actual

operating pressure at the sprays. Once the working relationship has

been established, the gauge pressure could be used to indicate the

actual spray pressure specified in the ventilation plan for a given

number of operating sprays.

Measurement of any required water flow rate could be accomplished

through the installation of a flowmeter. A flowmeter provides a direct

and reliable measurement and is the preferred method of determining

water flow rate. Another acceptable method of determining flow rate

would be to establish the relationship between the water pressure and

the spray orifice diameter, either through engineering data or through

actual tests. Once established, the water pressure gauge reading could

be used to reliably indicate a flow rate for a specific number of

sprays at a given orifice size.

The proposed requirement would specify that the number of water

sprays and their orientation be included in the examination. While

spray orientation is important in air-directing spray systems such as

sprayfans and shearer-clearers, the Agency does not intend that precise

angles be determined during each examination by the use of engineering

instruments. Rather, the correct direction and orientation of the

sprays would be determined by comparison with the requirements of the

ventilation plan.

The proposed requirement would also specify that the section

ventilation setup and control device placement be examined for

compliance with the ventilation plan. Information concerning section

ventilation systems is currently required to be contained in the

ventilation plan through Sec. 75.371(f). Any other respirable dust

control parameters specified in the approved ventilation plan would be

included in the examination under the proposal. An example could be the

cleaning and maintenance procedures for a wet bed scrubber installed on

a continuous mining machine.

Given the importance of and the need for continually maintaining

compliance with the dust control parameters to assure dust control,

dilution and removal, an effective system of continuous monitoring of

the performance and condition of the dust control parameters is

desirable. The Agency is aware that through advances in technology it

may be feasible to monitor air quantity and velocity, and spray water

flow rate and pressure. Continuous monitoring offers the potential to

further improve miner protection by providing real-time data on the

performance and condition of the dust control parameters. This

information can be used to give early warnings of deteriorating dust

control conditions which can be corrected before the dust control

system operates below the accepted standard. Although the application

of continuous monitoring will eliminate the need for periodic physical

measurements of key dust control parameters, visual observation will be

necessary to verify compliance with other ventilation plan parameters.

Among these are the number and location of operating water sprays,

their general condition and orientation, the section ventilation setup

and control device placement, and other control measures where

performance and operating condition can only be assessed visually.

Although the proposal includes continuous monitoring as an option,

the Agency is considering requiring the use of this technology at some

later date when it becomes available. Comments are solicited on this

approach. Specifically, comments are solicited on the parameters that

lend themselves to continuous monitoring, the need for performance

standards for monitoring devices, levels of detection, accuracy and

precision requirements for monitoring devices, the need for alarms and/

or warning signals when parameters monitored are outside of specified

tolerances, and the polling frequency necessary to provide monitoring

that is substantially continuous.

Paragraph (c)(1) would be modified to remove the word ``working''

modifying the word ``section'' in the current rule. The reason for this

proposed change is to achieve consistency between paragraphs (a) and

(c). Many of the activities to which persons are assigned would be on

sections not normally thought of as working sections, since the term

``working section'' is often associated with coal production. For

purposes of Sec. 75.362, a section in the mine is considered to be the

area inby the loading point, or the proposed loading point in the case

of the installation of equipment, or the location of the last

established loading point in the case of the removal of mechanized

mining equipment. The certified person conducting the examination would

examine the section in much the same way as it would be examined during

a coal producing shift, including checking for hazardous conditions,

testing for methane and oxygen deficiency, and determining if the air

is moving in its proper direction.

Paragraph (c) would require certified persons conducting on-shift

examinations to take the air measurements at the same locations where

air measurements are required during the preshift examination. This

would include areas where mechanized mining equipment, including

longwall or shortwall mining equipment, is being installed or removed.

This provides an additional check of the mine's ventilation system and

verifies that ventilation changes in the mine during the production

process have not occurred. Reduced volume or velocity of air during the

shift can contribute to increased levels of respirable dust and the

occurrence of methane accumulations or oxygen-deficient atmospheres.

The proposal includes an

This text is long and has been trimmed here. Open the source document for the complete record.