# Hazardous Materials: Requirements for DOT Specification Cylinders

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URL: https://www.frixlaw.com/law-library/documents/fr%3A98-28118

## Record

- **Collection:** Federal Register
- **Document type:** Proposed Rule
- **Published:** October 30, 1998
- **Citation:** 63 FR 58460

## Text

SUMMARY: RSPA proposes to amend certain requirements in the Hazardous
Materials Regulations (HMR) to establish four new DOT cylinder
specifications and to revise the requirements for maintenance,
requalification, and repair of all DOT specification cylinders. In
addition, RSPA proposes to: revise the requirements for approval of
cylinder requalifiers, independent inspection agencies, and nondomestic
chemical analysis and tests; revise the cylinder requalification,
maintenance and repair requirements; and to revise the requirements for
hazardous materials that are authorized to be offered for
transportation in cylinders. Finally, this NPRM incorporates a proposal
to remove from use aluminum alloy 6351-T6 that was published in an
advance notice under Docket HM-176A and terminates that docket (RIN:
2131-AB51).
This action is being taken to--simplify the HMR for construction of
cylinders; provide for flexibility in the design, construction and use
of cylinders; recognize recent advances in cylinder manufacturing and
requalification technologies; promote safety though simplification of
the regulations; reduce the need for exemptions; and facilitate
international commerce. The intended effect of this action is to
enhance the safe transportation of hazardous materials in cylinders.

DATES: Comment Date: Comments must be received on or before January 28,
1999.
Public Meeting Date: A public meeting will be held on December 8,
1998; from 9:30 am to 4:00 pm. An additional meeting may be scheduled
if there is substantial interest.

ADDRESSES: Written Comments: Address comments to the Dockets Management
System, U.S. Department of Transportation, PL 401, 400 Seventh St., SW,
Washington, DC 20590-0001. Comments should identify the docket number,
RSPA 98-3684(HM-220), and should be submitted in two copies. Persons
wishing to receive confirmation of receipt of their comments should
include a self-addressed stamped postcard. The Dockets Management
System is located on the Plaza Level of the Nassif Building, at the
above address.
Public dockets may be reviewed between the hours of 10:00 a.m. to
5:00 p.m., Monday thru Friday, excluding Federal holidays. In addition,
comments can be reviewed by accessing the DOT Homepage (http://
www.dot.gov). Comments may also be submitted by E-mail to
``[email protected]''. In every case, the comment should refer to the
Docket number set forth above.
Public Meeting: The public meeting will be held in Room 3200-3204
at the U.S. Department of Transportation's Nassif Building, 400 7th
Street SW, Washington DC, 20590.

FOR FURTHER INFORMATION CONTACT: Cheryl Freeman, telephone number (202)
366-4545, Office of Hazardous Materials Technology, or Ryan Posten,
telephone number (202) 366-8553, Office of Hazardous Materials
Standards, Research and Special Programs Administration, U.S.
Department of Transportation, Washington, DC 20590-0001.
SUPPLEMENTARY INFORMATION:

I. Background

Federal hazardous material transportation law (Federal hazmat law),
49 U.S.C. 5101-5127, authorizes the Secretary of Transportation to
regulate the manufacture and continuing qualification of packagings
used to transport hazardous materials in commerce, or packagings
certified under Federal hazmat law for the transportation of hazardous
materials in commerce. The HMR, 49 CFR parts 171-180, contain
requirements for the manufacture, use, and requalification of cylinders
subject to Federal hazmat law, including defining materials and methods
of construction, the frequency and manner of inspection and testing,
standards for cylinder rejection and condemnation, cylinder marking and
recordkeeping, authorizations for packaging hazardous materials in
cylinders, filling, loading, unloading, and carriage in transportation.
Historically, Federal authority to regulate the transportation of
compressed gases was given to the former Interstate Commerce Commission
(ICC) through the Transportation of Explosives Act, 35 Stat. 1135,
section 233 (March 4, 1909), which was later amended in 1921, at 41
Stat. 1445, Sec. 233. In 1911 the ICC adopted a series of ``Shipping
Container Specifications,'' among which the ICC 3 specification for
seamless steel cylinders was codified. That same year, the ICC 4
specification for a lap-welded cylinder for anhydrous ammonia was also
published. As the welding process improved, from the riveted/brazed
welds to resistance welding and then butt welding by the metal-arc
process, the ICC 4 Specification series was expanded to include the
4BA, the 4BW, and others. By 1914, two other cylinder specifications
were codified: the ICC 7 specification for steel cylinders for low
pressure, nonliquefied gas, (which have carried over to the present
regulations, but not as specification 7) and the ICC 8 specification
for acetylene gas cylinders, which still exists today with minor
changes.
In 1930, the ICC implemented regulations for periodic inspection
and testing of cylinders; the regulations, as amended, were first
published in the Federal Register on December 12, 1940 (5 FR 4908).
During the 1930's and 1940's, the Compressed Gas Association (CGA)
developed and refined the water jacket test method for determining the
serviceability of a cylinder. During World War II, there was a shortage
of high pressure gas cylinders. Because of CGA's work on steel wall
stress limitations, the ICC granted ``temporary'' regulatory relief to
increase the gas carrying capacity of existing cylinders by allowing
the cylinders to be filled 10% over their marked service pressures, and
by marking those cylinders with a plus, ``+'', mark. Ten years later,
the regulations were codified into the Code of Federal Regulations (15
FR 8261; Dec. 2, 1950). In 1967, pursuant to the Department of
Transportation Act, Pub. L. 89-670, 80 Stat. 931, regulatory
responsibility for the transportation of dangerous articles in commerce
was transferred from the ICC to DOT.
Through rulemaking and the issuance of exemptions from the
regulations under 49 CFR part 107, subpart B, materials other than
steel (e.g., aluminum and composite cylinders) now are authorized for
use. Nevertheless, apart from the substitution of the ``DOT''
identifier for the ``ICC'' identifier, many of today's basic
requirements remain virtually unchanged from the time they were first
incorporated into the regulations.
Over the years, RSPA has received numerous petitions for rulemaking
requesting various changes to the cylinder requirements. CGA filed most
of these petitions that request changes to

[[Page 58461]]

the cylinder specifications. In 1969, CGA submitted a petition (P-69)
containing six new proposals and revising eight previously-filed
petitions. Many of these 14 petitions were handled in subsequent
rulemakings such as Docket HM-69 adding a DOT 39 non-reusable, non-
refillable specification cylinder (August 24, 1971; 36 FR 16579),
Docket HM-85 updating the DOT-4L cylinder material properties (Nov. 5,
1971; 36 FR 21287), and Docket HM-99 adding the DOT-3T specification
cylinder (Aug. 15, 1973; 38 FR 21989).
In 1981, RSPA adopted a DOT 3AL specification under Docket HM-176
(46 FR 62452). This new specification for a seamless aluminum cylinder,
made of definitely prescribed alloys, was based in part on the
petitions received from industry and an agency initiative to
consolidate and eliminate the need for seven exemptions authorizing the
manufacture of seamless aluminum cylinders. In 1984, CGA petitioned (P-
953) to include a welded stainless steel cylinder similar to the DOT-
4BW. At that time, CGA proposed the designation ``4SS'' for the new
stainless steel cylinder.
In 1990, CGA petitioned to add a new 3F specification for a
seamless steel compressed gas cylinder designed for a high stress level
similar to the DOT-3T, but with a stronger structural integrity similar
to the DOT-3AA cylinder. The proposed 3FM specification provides for a
greater efficiency in gas transportation.
The above-mentioned petitions were given full consideration in the
development of this NPRM. In developing this NPRM, RSPA worked closely
with the cylinder manufacturing and maintenance industries, and held
several meetings with CGA to obtain clarification of the CGA petitions.
RSPA also held public outreach meetings with industry that were
announced in the Federal Register. The industry proposals and petitions
have been refined by RSPA based on RSPA's compliance inspections and
exemption program, interpretations issued by RSPA, and certain industry
consensus standards and practices that have proven to be safe. RSPA
believes the proposals in this NPRM are consistent with sound industry
practice and incorporate modern manufacture and requalification
technology.
Some of the more significant proposals contained in this NPRM are:
1. The establishment of four new cylinder specifications that are
more performance-oriented and the removal of several obsolete
specifications. These proposed specifications are expressed in metric
units, require marking of the cylinder with test pressure in place of
service pressure, and are distinguishable by their specification
designation markings.
2. The new specifications allows greater flexibility in the design
and construction of metric-marked cylinders.
3. Independent inspection of all metric-marked cylinders, both
seamless and welded.
4. Design qualification testing of metric-marked cylinders.
5. The requalification of metric-marked cylinders and certain
nonmetric-marked cylinders using thickness and shear wave ultrasonic
testing in place of the volumetric pressure test.
6. Requiring any person who performs a requalification function
that requires marking an inspection or retest date on the cylinder to
have approval from the Associate Administrator for Hazardous Materials
Safety (herein after referred to as the Associate Administrator).
7. Standardizing the requirements for the repair and rebuilding of
DOT 4 series cylinders, other than the DOT 4L.
8. Allowing a 10-year interval for requalification of DOT 3-series
metric-marked cylinders used in certain types of service.
9. Allowing a 15-year interval for requalification of certain DOT
4-series metric-marked cylinders used in certain types of service.
10. Allowing, upon approval by the Associate Administrator, the
application of requalification markings on cylinders by using
alternative methods that produce durable legible marks.
11. Implementing valve damage protection and puncture resistance
criteria for all DOT specification cylinders used for Division 2.3 or
6.1 materials in Hazard Zone B, and puncture resistance criteria for
those in Hazard Zone A.
12. Discontinuing authorization for a filled cylinder with a
specified service life from being offered for transportation in
commerce after its service life has expired.
13. Providing filling pressures for metric-marked cylinders based
on critical temperature, test pressure, and draft ISO Standard 11622.
14. Requiring that pressure relief devices on all metric-marked
specification cylinders be set at no less than test pressure. Requiring
that pressure relief devices on all 3-series, nonmetric-marked
specification cylinders be set at no less than test pressure from the
first requalification due after the effective date of the final rule.

II. New specification Standards for Metric-marked Cylinders

A. Consolidation of Cylinder Standards

As discussed above, the current cylinder requirements have their
origin in the early 1900's. The regulations were developed in a
piecemeal fashion, with adjustments being made to address particular
situations and problems on a case-by-case basis. This NPRM represents
RSPA's first comprehensive review of the cylinder requirements.
RSPA proposes to establish four new cylinder specifications for
seamless and welded cylinders. These proposed cylinder specifications
are more performance oriented and incorporate provisions that recognize
certain domestic and international practices. Cylinders made to these
specifications would be marked in metric units and would be
distinguished by a unique specification marking that closely
approximates the markings in draft International Standards Organization
(ISO) and the European Committee for Standardization (CEN), Technical
Committee, entitled ISO/TC58/SC4 ``Gas Cylinders Operational
Requirements,'' based on CEN Standard EN 1089-1, ``Transportable gas
cylinders--Gas cylinder identification--Part 1: Stampmarking.''
The new seamless cylinder specifications are identified as DOT 3M,
3ALM, and 3FM. The welded cylinder specification is identified as the
DOT 4M. Eventually, RSPA anticipates that the DOT 3M specification will
replace the current DOT 3A, 3AA, 3AX, 3AAX, 3B, and 3BN specifications.
The DOT 3ALM specification will replace the 3AL specifications. The DOT
3FM will replace the higher strength 3AA and the 3T specifications. The
DOT 4M will replace the 4B, 4BA, 4BW, 4B240X, 4B240ET, and 4E. In
future rulemakings, RSPA plans to propose new metric-marked cylinder
specifications to replace the current specifications for the DOT 3E,
3HT, 4D, 4DA and 4DS; the 4L; the 8 and 8AL; and the DOT 39.
The basic specification requirements, those common to most metric-
marked cylinders, are in proposed Sec. 178.69. This section contains
definitions, material of construction, duties of the inspector, and
criteria for all design and production qualification tests that may be
required by the individual specifications. Proposed Sec. 178.70
contains requirements applicable to seamless cylinders. The individual
specifications, containing additional requirements, are in Sec. 178.71
for the DOT 3M, Sec. 178.72 for the DOT 3ALM, and Sec. 178.73 for the
DOT 3FM. Proposed Sec. 178.81 contains

[[Page 58462]]

requirements applicable to DOT 4M welded cylinders.
In all cases where the new proposed specifications differ, the new
specification requirements will have a level of integrity that is
equivalent to, or greater than, the current nonmetric specification
requirements. Significant changes from current requirements are
discussed further in this preamble.

B. Cylinder Filling Limits

CGA petitioned RSPA to change the test pressure from 5/3 times
service pressure for currently authorized DOT specification seamless
cylinders to 3/2 times service pressure for newly constructed DOT
specification seamless cylinders. In effect, the CGA proposal would
increase the filling limit for most of the new seamless DOT
specification cylinders to that currently authorized for cylinders
marked with a ``+'' sign (see 49 CFR 173.302(c)). In the historical and
technical information provided to support its petition, CGA stated:

I. Background

In 1942 during the height of industrial production for WWII, a
shortage of high pressure gas cylinders developed. The shortage was
hampering the War effort. The three manufacturers of large size
cylinders were also forging shells and bombs and did not have
capacity to forge those and the required quantities of high pressure
steel cylinders.
The War Production Board brought this concern to the Compressed
Gas Association (CGA) to seek a remedy for the shortage of high
pressure cylinders. One idea was to start up new production by
spinning seamless tubing, which was initiated by Cueno-Press and
Taylor Forge; but that would take months. An immediate ``temporary''
relief was conceived which was to increase gas carrying capacity by
allowing an ``overfill'' of existing cylinders. After careful study,
the increase of 10% in filling pressure (i.e., from 2015 to 2215
psi) was considered safe and technically sound because of the
conservative design required by DOT Specification 3A and of the
existing high pressure cylinders produced thereto.
For example: A 10% increase in wall stress at the increased
filling pressure maintained the operating stress well below the
yield point of the steel; and so, cyclic fatigue failure would not
become a factor for the ductile, low strength steel. Furthermore,
the operating stress would still be far below the ultimate tensile
strength providing an adequate safety factor which related service
pressure to rupture pressure; and the only way the cylinder pressure
of permanent gases could reach burst pressure was by involvement in
a fire.
By joint agreement between the War Production Board, Interstate
Commerce Commission (ICC) and the Gas Industry, it was decided to
immediately allow a ``10% overfill'' for the existing cylinder
fleet. This was to be allowed for both flammable and non-flammable
permanent gases.
To make this effective required a change in the ``Regulations''
covering ``Charging of Cylinders with Non-liquefied Compressed
Gases'' because it was to be applied to existing cylinders as well
as new production. Therefore, section 173.302 was changed and 178
was not changed to cover cylinder design and production. Thus, a 10%
increase in the gas carrying capacity of the existing cylinder fleet
and new current production was immediately achieved. This had the
effect of adding 10% additional cylinders.

II. Technical Rationale for Allowing 10% Higher Fill Pressures

A. Introduction

The fleet of DOT 3 Series cylinders in use during the war years
performed safely without a service failure, notably from fatigue or
gas pressure rupture. Thus, the carefully considered decision to
allow the charging pressure to be increased by 10% was considered to
be proven safe and technically valid.
The compressed gas industry monitored performance of their
cylinder fleets and concluded that the ``temporary'' over-filling
procedure could safely become a permanent regulation. However, CGA
decided to recommend certain controls to justify permanent
continuation of this change which effected the design safety factor.
Those controls are now contained in CFR Title 49, clause 173.302 (c)
entitled ``Special filling limits for Specification 3A, 3AA, 3AX,
3AAX and 3T cylinders''.
The technical rationale for those controls was: * * *
(1) ``That such cylinders are equipped with frangible disc
safety relief devices (without fusible metal backing) having a
bursting pressure not exceeding the minimum prescribed test
pressure.''
Rationale: This was to guarantee that cylinder pressure from any
source could never reach the cylinder design burst pressure.
Therefore, lowering the ratio of service pressure to rupture
pressure, was meaningless because the cylinders would be equipped
with a ``rupture port'' which would vent the gas pressure at a pre-
determined pressure and prevent the cylinder from ever reaching its
``burst'' pressure. * * *
(2) ``That the elastic expansion shall have been determined at
the time of the last test or retest by the water jacket method.''
Rationale: In the 1930s and 1940s the CGA had developed and
refined the water jacket test method, and developed the mathematical
relationship of wall stresses as measured by the elastic expansion
of individual cylinder designs. The average wall stress as
determined by elastic expansion measured by the water jacket
hydrostatic test was limited to a specified stress less than the
permitted maximum design stress. For example, 3AA design cylinders
were to be rejected if the elastic expansion exceeded a value
equivalent to the strain developed at an average wall stress of
67,000 psi; whereas, the design wall stress limit in 178.37-10(b) is
70,000 psi. This 4% decrease in wall stress was selected because
elastic expansion measures the average effective wall thickness and
not the minimum. At the same time it was concluded that a small
increase (i.e., 4%) in the stress at isolated areas of a cylinder
could be safely tolerated to allow for localized damage or thinning;
and a ``Maximum wall stress limitation'' was set; e.g., 73,000 psi
for 3AA design cylinders. This procedure of elastic expansion
control was developed to further justify the permanent use of the
``10% overfill'' by guaranteeing that such cylinders would be
controlled by limiting the loss of wall thickness so that the stress
at service pressure would be below the yield point of the cylinder
steel. * * *
(3) ``That either the average wall stress or the maximum wall
stress shall not exceed the wall stress limitations shown in the
following table.''
Rationale: Wall stress limitations for both average wall and
isolated spots were developed for each ``class of steel'' used for
ICC 3, DOT 3A, and DOT 3AA cylinder designs. (Much later DOT-3T was
added.) These limits were selected from known physical properties of
these steel classes; and were set to assure that stress at operation
pressures were: (1) well below yield point and (2) that an adequate
burst pressure to service pressure ratio was obtained. This clause
amplifies the preceding clause 2.
(4) ``That an external and internal visual examination made the
time of test or retest shows the cylinder to be free from excessive
corrosion, pitting, or dangerous defects.''
Rationale: The body of data and service experience available
within the CGA had proven that the design criterion for DOT high
pressure cylinders was eminently safe; especially as regards cycle
life and rupture in service. The only cause of cyclic or tensile
rupture would be damage inflicted during manufacture or service.
Thus, the visual inspection before and during use was considered to
be an essential safety measure, which continues to be true today.
(5) ``That a plus sign (+) be added following the test date
marking on the cylinder to indicate compliance with paragraphs (c)
(2), (3) and (4) of this section.''
Rationale: This was to force both the cylinder manufacturer and
user to take a physical act to signify their guarantee of compliance
with the control methods. This also was an easily discerned mark
that permitted personnel to identify which cylinders were
satisfactory, safe and qualified for charging to the ``10%
overfill''.

B. Wall Stress and Safety Factors of Series 3 DOT Cylinders

The most common high pressure cylinder in use in 1942 was the
ICC-3A-2015 with size of 9'' O.D. x 51'' long, rated at 220 cubic
feet oxygen capacity. This cylinder made of normalized intermediate
manganese steel had an ultimate tensile strength of about 95,000 psi
and had excellent ductility and good charpy impact strength at
-50 deg.F. to assure safe fracture performance. The design stress at
test pressure was 49,500 psi which with the 5/3 test pressure ratio
allows a stress of 29,600 psi at 2015 psi service pressure. The
yield point was about 69,000 psi (about 0.73 x U.T.S.). Thus the
service stress was about 50% of yield stress, which level assured a
long (virtually infinite) cycle life. The burst stress to service
stress ratio (safety factor) was about 3.2 (95,000
29,600).* * *

[[Page 58463]]

This ratio of operating stress compared to ultimate strength was
obviously a conservative design. The conservatism is more obvious in
view of the fact that the cylinders were seamless, forged, high
quality steel pressure vessels which have no stress concentration
points in the longitudinal plane of major stress. Furthermore, they
were used in non-corrosive gas service and have no source to
increase the contained pressure during use except by the small
fluctuations in ambient temperature or a fire. The cylinders are
also subjected to periodic requalification. In view of these facts/
data and the excellent service record, the decision was made in 1942
to allow stress to increase about 32,600 psi at service pressure for
the ``10% overfill''. This equates to a working stress to burst
strength ratio of 2.9 (95,000 32,600).
Thus the ``10% overfill'' was considered technically appropriate
and eminently safe as a way to increase the oxygen carrying capacity
from 220 CF to 244 CF. These cylinders have continued in service for
over 50 years with a perfect safety record as regards cyclic or
pressure rupture in service. The same effective stress at test
pressure can be achieved by testing either at 5/3 of 2015 or 3/2 of
2215. These pressures are 3358 and 3323 which stresses the wall to
49,350 and 48,720 psi respectively. This 1.2% difference in test
pressure stress would be inconsequential with respect to cylinder
safety. Therefore, the test pressure in the DOT 3A, 3AA, and 3T
specifications can safely be changed to 3/2 instead of 5/3 service
pressure. The following paragraph describes graphic presentation of
the situation with intermediate manganese normalized and chrome-moly
quenched and tempered, which represents virtually 100% of the 3A and
3AA cylinders in the U.S. * * *
It is proposed to write all the ``10% overfill'' into the design
conditions for DOT 3A, 3AX, 3AA, 3AAX, 3F (new) and 3T. This can be
accomplished by merely changing the required test pressure from 5/3
x service pressure to 3/2 x service pressure. For all intents and
purposes, the cylinders would be exactly the same as discussed
above. * * *

III. Conclusions

1. DOT 3A and 3AA cylinders have been in use since 1942 (54
years) with a ratio of test pressure to service pressure of 3/2. At
time of manufacture or retest, the cylinders are tested at 5/3 x
service pressure; but the service pressure is increased by 10% for
filling.
2. The 10% overfill pressure times 3/2 results in a wall stress
at test pressure only 1% less than the requirement to test at 5/3
times marked service pressure.
3. The 3/2 test pressure would result in a calculated minimum
wall of barely 0.001 inch less for a current cylinder with a 0.250
wall minimum.
4. The tiny decrease in wall thickness and effect of 1% lower
stress at test pressure would have no effect in overall cylinder
safety.
5. The service record since 1942 (54 years) has been perfect as
regards rupture under gas pressure and cyclic fatigue
characteristic. The change to 3/2 test versus 5/3 does not change
any measurable characteristic which would effect these failure
modes.
6. The ASME Code uses a 3/2 test pressure to working pressure
ratio.
7. Europe (18 countries) uses the 3/2 test to service pressure
ratio.

IV. Recommendation

The minimum prescribed test pressure shall be 3/2 times the
marked service pressure for all cylinders with a marked service of
500 psi or greater for all Series 3 steel cylinders. This should
also be considered for cylinders made of nickel, aluminum or
stainless steel.

In considering the issue of cylinder filling limits, RSPA also
reviewed technical information supplied by cylinder manufacturers and
by holders of exemptions that authorize either a test pressure of 3/2
times service pressure or 10% overfill for materials not currently
specified in 49 CFR 173.302(c), the hazardous materials information
system data base for incidents involving ``+'' marked cylinders, and
the work currently being done by the ISO and the United Nations Group
of Experts on the Transport of Dangerous Goods. After reviewing all the
available information, RSPA has concluded that from a transportation
safety perspective, there is no technical reason or safety experience
which would prohibit increasing the cylinder filling limits for
seamless cylinders to those comparable to the levels currently
authorized in 49 CFR 173.302(c). Therefore, RSPA has accepted the CGA
proposal to increase the filling limits for new cylinders, in
principle, but has chosen to limit the proposal for increased filling
limits to metric-marked DOT Specification cylinders. Additionally, RSPA
has not changed the requirements in 49 CFR 173.302(c) for the current
DOT specification cylinders, but has moved them to proposed
Sec. 173.302a(b).
With regards to existing cylinders, RSPA is considering a process
for accepting certain DOT specification cylinders as meeting the new
metric specifications, but is still considering various conversion
criteria. RSPA solicits comments from interested persons as to the
interest and feasibility of developing such a conversion program and,
if feasible, specific criteria for requalifying and conversion of
existing cylinders.

C. Specification Markings on Metric-marked Cylinders

In the CGA submission to RSPA, it was requested that cylinders be
marked in bar rather than psig. Bar is an internationally accepted
metric unit for pressure in the compressed gas industry. This change
would help make marking DOT specification cylinders consistent with the
practice in most European countries which are currently marking
cylinders with the test pressure shown in bar.
While considering this request, RSPA reviewed its current marking
requirements as well as two draft documents on the subject of cylinder
marking being considered by the ISO and the CEN. The documents are ISO/
DIS 13769, ``Gas cylinders--Stamp marking,'' and CEN Standard EN 1089-
1, ``Transportable gas cylinders--Gas cylinder identification--Part 1:
Stampmarking.''
Based upon this review, RSPA proposes to change the way DOT
specification cylinders are marked. The new marking scheme will change
the number and sequence of marks required to be placed on DOT
specification cylinders by manufacturers and is consistent with the
sequence being proposed by both ISO and CEN. However, RSPA does not
proposed to require all of the cylinder marks contained in either the
ISO or CEN documents. The proposed marking scheme will also make it
easier to identify those cylinders manufactured to the proposed
specifications. Additionally, the marking scheme is similar to the type
of marking scheme contained in the United Nations Recommendations for
the Transport of Dangerous Good for non-bulk packagings and
intermediate bulk containers.
The proposed marking sequence, with each element separated by a
slash mark, is as follows:

DOT Specification
Country of origin
Manufacturer's identification
Serial number
Stamp for non-destructive testing (if applicable)
Minimum wall thickness
Water capacity (liters)
Test pressure (bar)
Identification of alloy
Tare weight (kg)
Identification of inspection agency
Test date
REE (if applicable)

The most significant change is the marking of the new specification
cylinders with test pressure instead of service pressure. DOT
specification cylinders have always been designed to test pressure
rather than service pressure. Specifically, the stress formulas used to
determine the minimum wall thickness of DOT specification cylinders are
calculated at the minimum test pressure.

[[Page 58464]]

Additionally, as currently authorized in 49 CFR 173.302(c), many
cylinders used to transport compressed gases which are not liquefied,
dissolved, toxic or flammable are filled to a pressure 10% in excess of
their marked service pressure and 49 CFR 173.304(f) specifies, with
limited exceptions, that the pressure in the container at 130 deg.F
shall not exceed 5/4 times the marked service pressure. While marking
the test pressure rather than the service pressure will require the
training of persons who fill cylinders, it should not have any adverse
safety effects since inadvertently filling a cylinder to the marked
test pressure, in bar, would result in the cylinder being filled to a
lower pressure than the currently marked service pressure in psig.
Further, most cylinders are filled by a person who uses a filling table
that shows the values already adjusted for changes in temperature and
elevation. RSPA envisions that cylinders marked with test pressure will
also be filled by using filling tables.

III. Independent Inspection--New DOT Specification Cylinders

A DOT specification cylinder is, and has been for the past sixty
years, a widely recognized standard for the safe transportation of
compressed gases. This wide acceptance has resulted in significant
economic benefit to domestic industry far beyond the value of the
cylinders sold internationally. Market demand for gases and equipment
has increased as a direct result of the reputation of the DOT cylinder
for strength, durability and quality.
Since the early 1900's, cylinders manufactured under DOT's ``high
pressure'' specifications have required independent inspection,
originally referred to as ``disinterested inspection.'' Occasionally,
RSPA receives complaints from companies about costs of independent
inspection or claims that the companies' employees are as knowledgeable
and qualified, if not more so, as the independent inspector. However,
RSPA's Office of Hazardous Materials Enforcement, through its
compliance inspection program, has found a higher level of compliance
with the regulations when inspection and certification functions are
carried out by an Independent Inspection Agency (IIA) instead of by an
employee of the manufacturing company. In order for DOT specification
cylinders to be acceptable for service in most foreign countries,
cylinders must be certified through an inspection process which is not
controlled by the cylinder manufacturer. Since 1977, all DOT
specification cylinders manufactured outside the United States under
the RSPA foreign cylinder approvals program are required to be
inspected and certified by an IIA.
In order to maintain the high level of safety established over the
past 100 years, to maintain the acceptability of DOT specification
cylinders worldwide, and to facilitate the harmonization between
domestic and foreign cylinder specifications, RSPA is proposing that
all cylinders manufactured or rebuilt to the new DOT metric-marked
cylinder specifications be subject to inspection by an IIA. In effect,
this would continue the current DOT inspection requirements for
seamless cylinders and extend the practice to welded cylinders.

IV. DOT Approval of Cylinder Requalifiers

RSPA proposes that any person who requalifies a DOT specification
cylinder must be approved by the Associate Administrator prior to
performing any requalification function that requires an inspection or
retest date to be marked on the cylinder. The affected functions
include performance of a visual inspection, pressure test, ultrasonic
thickness test, repair, or the rebuilding of cylinders. This proposal
will enhance the accountability of the cylinder requalification
process.
Currently, Sec. 173.34(e)(13) permits a cylinder used exclusively
for certain liquefied gases to be requalified for use by performing an
external visual inspection and marking the cylinder with the test date
and an ``E''. The ``E'' indicates that the cylinder was requalified by
external visual inspection in accordance with CGA Pamphlet C-6 rather
than by a hydrostatic test. A person who performs only external visual
inspections is not required to obtain an approval from, or register
with, the Associate Administrator. Although current Sec. 173.34(e)(13)
requires these persons to maintain records, RSPA does not know who or
how many persons requalify and mark cylinders with an inspection date
and an ``E'', or the locations of their places of business. Also, RSPA
does not know whether these persons have the knowledge and skills
necessary to perform the required functions, including use of required
inspection standards.
RSPA inspectors have frequently observed DOT specification
cylinders, primarily in liquefied petroleum gas service, that bear
markings representing that they were requalified for use. The markings
reflected dates of recent requalification by external visual
inspection. One cylinder, marked with the letter ``E'' and the date ``6
98,'' was examined by RSPA personnel on June 19, 1998, and found to be
rusted to an extent that there is no doubt that the rust formed long
before the marked inspection date. Considering the amount of
undisturbed rust on the cylinder, it was apparent that the person
requalifying the cylinder did not properly prepare it for inspection by
first completely removing all rust from the exterior surface of the
cylinder, as required by paragraph 3.1 of CGA Pamphlet C-6, which was
developed by the compressed gas industry for adoption by reference as
Federal regulations.
In reviewing the approach for resolving this issue, RSPA considered
five options:
(1) Continue the current provision that allows persons who are not
known to RSPA to requalify cylinders by performing visual inspections;
(2) Adopt a registration program that would require persons who
perform visual requalification to be registered with RSPA and to mark
their requalifier identification numbers (RIN) on the cylinders they
inspect;
(3) Adopt an approvals program requiring that persons performing
requalifications of cylinders by visual inspection be approved by RSPA
upon written application containing statements regarding their
qualifications;
(4) Adopt an approvals program that would require persons
performing visual requalifications to be reviewed by an independent
inspection agency; and
(5) Discontinue visual requalification of cylinders, thereby
requiring all affected cylinders to be hydrostatically retested.
RSPA selected option 3 for this NPRM because it will not impose the
burden and added cost of employing an independent inspection agency
while ensuring the accountability of a person performing visual
requalifications and providing RSPA the authority to revoke or suspend
the person's approval for demonstrated non-compliance with the
requalification requirements. Also, by requiring a certification that
an applicant has the ability to perform requalifications, RSPA believes
each applicant's awareness of the importance of compliance will be
heightened. RSPA solicits comments on these options and others that
RSPA may not have considered.

V. Requalification Markings

RSPA proposes to amend Sec. 171.2(d) to prohibit the
misrepresentation of a requalification identification number (RIN)
marking. Over the years, through its compliance program, RSPA has been

[[Page 58465]]

in contact with dozens of individuals who did not perform the required
hydrostatic tests, but stamped the cylinders as though each cylinder
had passed the inspections and tests. The steel stamps used to mark the
cylinders are readily available, low-cost and simple to use. RSPA
believes that these and other factors (e.g., the high cost of
purchasing and maintaining hydrostatic test equipment when compared to
the mere cost of obtaining a set of steel stamps) provide an economic
inducement for some individuals to engage in fraudulent activities.
Based on recent enforcement data, this safety problem appears to be
more widespread than RSPA originally thought. RSPA is concerned about
the number of cylinders that are fraudulently stamped and then are used
to transport hazardous materials in commerce. These cylinders, whose
structural integrity has not been verified, pose substantial risks to
health, safety and property. When RSPA discovers these situations, RSPA
publishes a safety alert notice (see Notice No. 97-2, 62 FR 19651;
Notice No. 97-3, 62 FR 24548) and, where appropriate, refers the matter
to the Department of Justice for possible criminal prosecution (see
United States v. American Oxygen Company, et al., Docket No. 97-533
(D.N.M.)).
RSPA is also soliciting comments on the issue of what future method
or methods should be used to mark DOT specification cylinders during
the requalification process. Currently, after a cylinder meets the
requalification standards (e.g., passes a hydrostatic test, internal
and external visual examinations, etc.), the requalifier stamps the
month and year of the test and its RIN on the cylinder. This marking is
normally accomplished with steel stamps (Note: currently under an
exemption certain fiber-wrapped cylinders may be marked with labels.).
Through this rulemaking, RSPA is evaluating the merits of new marking
methods for DOT specification cylinders following the requalification
process.
RSPA is considering incorporating a number of marking options
(e.g., labeling, marking with a laser, replacing the RIN with a symbol
that is difficult to duplicate, etc.). RSPA is requesting comments from
the public as to the feasibility, costs and benefits of alternatives to
the metal stamping method and whether the public believes there is
justification for RSPA adopting an alternative method.

VI. Toxic Gases

Division 2.3 and 6.1, Hazard Zone A and B toxic inhalation hazard
(TIH) materials present a substantial risk to the public, transport
workers and emergency responders even when small quantities are
released. For smaller cylinders, shifting freight and dropping are
major sources of package damage and releases of hazardous materials.
Cylinders are sometimes dropped in handling, resulting in valve damage
or cylinder punctures. In a study of Hazardous Materials Information
System (HMIS) reports for the past 10 years, RSPA found that over 30%
of all reported cylinder incidents involved valve damage. Valve damage
occurs when valves are inadequately protected by outer packagings or
valve protection devices. Punctures most commonly occur when a cylinder
is impacted by handling equipment or other cargo or is dropped upon
other cargo or handling equipment. To reduce the probability that a
handling incident may result in the release of a TIH material, RSPA
proposes to expand the current drop test requirement for cylinders
containing TIH materials to include Hazard Zone B materials and a
performance test for cylinder puncture for TIH materials in Hazard
Zones A and B. These proposed performance tests apply to bare cylinders
and cylinders packed in strong outside packagings.
The performance test for puncture is based upon dropping a cylinder
seven feet; the same height used in the drop test for cylinder valve
protection. The seven-foot drop height represents the typical distance
that an industrial gas cylinder would encounter if it fell from a
truck. RSPA chose an angle iron (2 inch by 2 inch by 0.25 inch thick)
as a typical penetrator. The major parameters controlling cylinder
penetration are cylinder material, wall thickness, drop height and the
cylinder's gross weight. For consistency, RSPA proposes the cylinder
weight be the water-filled weight. To represent in-service stress
conditions, the proposed test is performed on the filled cylinder
charged to service pressure for nonmetric-marked cylinders and 67% of
test pressure for metric-marked cylinders.
The puncture-performance test would be required for metric-marked
and nonmetric-marked cylinders. To facilitate implementation of this
requirement for nonmetric-marked cylinders, RSPA is proposing a two-
year implementation period. RSPA also proposes a table showing
threshold values of wall thickness for cylinders of a particular
specification, material, and water-filled weight range. Cylinders
meeting the specified criteria with a minimum side wall thickness equal
to or greater than the value specified in the table would qualify under
current Sec. 173.40(d)(1) without puncture testing. To minimize the
testing burden, RSPA plans to perform puncture testing to develop
initial values for the table. RSPA is requesting that cylinder
manufacturers and shippers assist RSPA in developing this table. RSPA
is also soliciting comments on whether welded cylinders and cylinders
with wall thickness of 2.0 mm or less are used for the transportation
of Division 2.3 and 6.1 Hazard Zone B, C, and D materials. RSPA will
use this information to further develop the puncture testing threshold
table. When sufficient data is available, RSPA would consider the
development of a graph or calculation as a more practical means to
depict a minimum thickness threshold for puncture resistance.

VII. Discontinuation of Certain Cylinder Specifications

RSPA proposes to discontinue the use of the following DOT cylinder
specifications: 3C, 3D, 4, 4A, 4B240X, 4B240FLW, 4C, 9, 25, 26, 33, 38,
40 and 41. RSPA believes that these cylinders are obsolete and no
longer in general use. Authorization to manufacture these cylinders was
removed from the regulations on September 11, 1980 (45 FR 59887).
Comments are solicited from persons who may be using these cylinders.
If the proposals contained in this NPRM lead to publication of a
final rule, RSPA proposes to provide a transition period of five years
from the effective date of the final rule for the continued
construction of cylinders made to the following DOT specifications: 3A,
3AX, 3AA, 3AAX, 3AL, 3B, 3T, 3BN, 4B, 4BA, 4BW, 4B240ET, and 4E. RSPA
believes a five-year transition period for new construction of
cylinders conforming to these specifications will reduce the burdens
incurred by persons affected by this proposal. Cylinders made to these
specifications would be authorized for continued use as long as they
meet standards for periodic requalification. Voluntary compliance with
the new metric or revised requirements would be authorized 90 days
following publication of the final rule in the Federal Register.

VIII. Pressure Relief Device (PRD) Systems

In a previous rulemaking (see, Docket No. HM-220A, 61 FR 26750,
26756; May 28, 1996), RSPA proposed voluntary compliance with CGA
Pamphlet S-1.1, paragraph 9.1.1.1, which would require verification
that the PRDs operate properly. RSPA made this proposal based on the
view that

[[Page 58466]]

over time certain components within a PRD will cease to function as
designed. Thus, RSPA proposed adopting paragraph 9.1.1.1 which would
have required that the operation of the PRD be verified. A number of
commenters opposed this proposal citing its cost and the lack of
incident data supporting adoption of this requirement. Based on the
need to gather more data and review the cost estimates submitted, RSPA
withdrew the proposal and agreed to consider the proposal in a future
rulemaking. RSPA continues to evaluate adopting this industry standard.
Since publication of HM-220A final rule, gas industry
representatives have expressed the view that over time most polymers,
used as seats in PRDs, vulcanize. Vulcanization prevents the devices
from functioning as designed. RSPA solicits information on the
following:
1. Data and comments on the cost, effectiveness and need for
adopting paragraph 9.1.1.1, in CGA Pamphlet S-1.1.
2. Additional incident data from State and local officials
concerning incidents that involved compressed gas cylinders which may
not have been reported to RSPA because the incident did not involve a
hazardous materials carrier or did not meet the reporting criteria
specified in 49 CFR Sec. 171.16.
3. Comments on the need to require PRD manufacturers to certify a
performance range and period for their devices. Thus, a PRD would have
to perform within specific limits throughout a specific life.
Public comments that address these issues will be considered in a
future rulemaking.

IX. Related Rulemakings, Petitions for Rulemaking, and Safety
Recommendations

Docket HM-176A (RIN 2131-AB51). RSPA proposes to amend Sec. 178.46
to remove aluminum alloy 6351-T6 as an authorized material for the
manufacture of DOT 3AL seamless cylinders. In January 1990, at RSPA's
urging, manufacturers of DOT 3AL cylinders voluntarily discontinued the
use of aluminum alloy 6351-T6 because cylinders made of this alloy are
susceptible to cracks that could result in leaks or ruptures.
On July 10, 1987, RSPA published in the Federal Register a safety
advisory and advance notice of proposed rulemaking (ANPRM) (Docket No.
HM-176-A; 52 FR 26027) to inform all persons possessing DOT 3AL (49 CFR
178.46) cylinders, made of aluminum alloy 6351 manufactured by Luxfer
USA Limited, that cracks had developed during service which
occasionally resulted in leakage and loss of cylinder contents. In
addition to the safety advisory, the notice identified those cylinders
at risk, suggested steps that users should take to minimize risks, and
requested industries' comments concerning the extent of the problem and
their suggestions on corrective measures.
RSPA received 31 comments from manufacturers, distributors, and
industrial users of aluminum alloy cylinders. Some commenters submitted
findings of studies for cylinders manufactured with aluminum alloy
6351, including sustained load cracking (SLC) behavior testing. The
majority of the comments and findings concluded that DOT 3AL cylinders
made from aluminum alloy 6351, including cylinders authorized under
exemption DOT-E 7235, pose a greater probability of failure than other
cylinders. Further, information available to RSPA reveals that it is
difficult to detect cracks in these cylinders which adds to the risks.
RSPA published several notices to alert persons to the safety risk
associated with cylinders manufactured to the DOT 3AL specification or
under exemption DOT E-7235 and containing alloy 6351 (50 FR 32944,
August 15, 1985; 58 FR 15895, March 24, 1993, 59 FR 38028, July 26,
1994). Thus, there is sufficient data which demonstrates that this
alloy is not suitable for the manufacture of compressed gas cylinders
and that it should be removed as an authorized construction material.
Petitions for rulemaking. RSPA has received numerous petitions for
rulemaking requesting changes to the cylinder specifications and
related commodity and requalification requirements. These petitions
were held in abeyance and were considered in the development of this
NPRM. Most of the requested changes are included in this NPRM. Because
of the proposals in this NPRM to establish four new cylinder
specifications and to discontinue construction of cylinders to certain
current specifications, some of the requests for changes to the current
regulations are no longer warranted. A summary of the petitions, with
RSPA's comment shown in brackets, are as follows:

----------------------------------------------------------------------------------------------------------------
Petition No. Request
----------------------------------------------------------------------------------------------------------------
0095................................... Consolidate the DOT 3-series specifications to permit unified
specifications. Filed by CGA [Proposed in Secs. 178.69-178.73 for
metric-marked cylinders].
0154................................... Permit filling of non-toxic, nonliquefied flammable gases to 110% of
the cylinder's marked service pressure (including hydrogen). Filed by
CGA [Proposed in Sec. 173.302b for metric-marked cylinders].
0312................................... Align rejection criteria of welded cylinder specifications to permit
testing of second specimen from same lot if first specimen fails.
Filed by the Canadian Transport Commission [Proposed in Sec. 178.81
for metric-marked cylinders].
0324................................... (Request same as P-0312). Filed by the Association of American
Railroads.
0457................................... Revise cylinder repair and rebuilding requirements. Filed by CGA
[Proposed in Sec. 180.211 for all cylinders].
0553................................... Amend Part 178 to change cylinder lot size in each specification. Filed
by CGA [Proposed in Sec. 178.70 for seamless metric-marked cylinders
and in Sec. 178.81 for metric-marked welded cylinders].
0652................................... Revise Sec. 173.302(c)(3) table to add a fifth class of steel for DOT
3 series cylinder tubes. Filed by CGA [Proposed in Sec. 178.70 for
metric-marked cylinders].
0752................................... Amend the table in 178.37-5(a), by adding a column titled ``Authorized
Chemical analysis (designation 10B30).'' Filed by Pressed Steel Tank.
(See DOT E 8311) [Proposed in Sec. 178.70 for metric-marked
cylinders].
0823................................... Incorporate by reference CGA Pamphlets C-1 and C-5. (See also P-981).
Filed by CGA [Incorporated by reference in Sec. 171.7].
0866................................... Revise required sequence for display of specification markings on
seamless aluminum cylinders and allow use of new marking techniques
[Proposed in Sec. 178.69 for metric-marked cylinders].
0953................................... Establish a new specification for manufacture of new welded, stainless
steel cylinders. (See E-4884). Filed by CGA [Proposed in Sec. 178.81
DOT 4M specification].
1040................................... Revise Sec. 173.304(c) and (d)(4) to expand specific gravities for
LPG, at 42% filling density, from 0.504-510 to 0.497-0.510. Filed by
the National Propane Gas Association [Proposed in Sec. 173.304b for
metric-marked cylinders].
1071................................... Permit use of DOT 3AL cylinders for any gas or gas mixture that is
compatible with aluminum. Filed by CGA [Proposed greater use DOT 3ALM
cylinders in Sec. 173.302b].

[[Page 58467]]

1082................................... Revise 173.302(f) to remove 5/6 filling pressure limitation applicable
to DOT 3AL cylinders. Filed by CGA [Proposed in Sec. 173.301a for DOT
3AL cylinders and in Sec. 173.301b for DOT 3ALM cylinders].
1087................................... Establish a new specification for seamless steel cylinders having a
design stress of not more than 90,500 psi and a water capacity of not
more than 150 pounds. (E-9001, 9370, 10047). Filed by CGA [Included in
proposed new DOT 3FM specification in Sec. 178.73].
1090................................... Require that a cylinder requalified by visual inspection must be marked
with the retester's identification number. Filed by CGA [Proposed in
Sec. 180.213].
1189................................... Establish a new low pressure welded stainless steel cylinder
specification. Filed by CGA. Includes P-0953 [Proposed in Sec. 178.81
DOT 4M specification].
1229................................... Revise Secs. 178.36 thru 178.60 to specify procedures for conducting
tensile test. Filed by CGA [Proposed in Sec. 178.69 for metric-marked
cylinders].
1233................................... Permit nondestructive requalification testing of compressed natural gas
(CNG) cylinders. Filed by FIBA [Proposed in Secs. 178.69, 180.207 and
180.209 for metric-marked cylinders and certain nonmetric-marked
cylinders].
1263................................... Revise Sec. 173.34(e)(18) to permit the use of a permanent, non-
transferrable label for retest and inspection markings on fire
extinguishers. Filed by Amerex [Proposed in 180.213].
1277................................... Revise Sec. 173.34(i)(4) to except DOT 4BW cylinders from heat
treatment after replacement of nonpressure attachments. Filed by
Manchester [Proposed in Sec. 180.211 subject to certain conditions].
----------------------------------------------------------------------------------------------------------------

National Transportation Safety Board (NTSB) Safety Recommendations.

I-92-001
Recommends that RSPA require attachments to all DOT authorized
hazardous materials packagings be designed to minimize the risk of
puncturing other hazardous materials packagings during an accident
situation. (Proposed in Sec. 173.301(m))
I-90-008
Recommends that RSPA require hazardous material cargo to be secured
in transportation with adequate restraint systems to prevent ejection
of cargo from vehicles. (Proposed in Sec. 177.840)
I-90-009
Recommends that RSPA require independent inspection of new and
reconditioned low pressure cylinders that are consistent with present
independent inspection requirements for high pressure cylinders
[Proposed for 4M cylinders in Sec. 178.69.]

X. Cross Reference Table

The following table lists the proposed paragraphs or sections and,
where applicable, the corresponding paragraph or section contained in
the current HMR. In some cases, the cross references are to provisions
which are similar to, but not identical with current provisions.

------------------------------------------------------------------------
New section Old section
------------------------------------------------------------------------
107.801
107.803(a)................................ 173.300a(a).
(b)..................................... 173.300a, 173.34(e)(2)(ii)
third sentence.
(c) intro............................... 173.300a(b).
(c)(1).................................. (b)(2).
(c)(2).................................. (b)(3).
(c)(3).................................. (b)(6).
(c)(4).................................. (b)(7).
(c)(5).................................. (a).
(c)(6)
(c)(7)
(d)..................................... (c), (i).
107.805(a)................................ 173.34(e)(2)(ii).
(b)..................................... (e)(2)(ii).
(c)..................................... (e)(2)(ii)(A).
(d)..................................... (e)(2)(ii)(B).
(e)..................................... (e)(2)(ii)(B).
(f)
107.807(a)................................ 173.300b.
(b)..................................... (b).
(c)..................................... (g).
173.301(a)
(a)(1).................................. 173.301(h).
(a)(2).................................. 173.34(e)(1).
(a)(3).................................. (e)(17).
(a)(4).................................. (a)(2).
(a)(5).................................. (e)(1)(ii).
(a)(6).................................. 173.301(k).
(a)(7)
(a)(8)
(a)(9)
(a)(10)................................. 173.301(k).
(b)..................................... 173.34(c).
(c)..................................... 173.301(a).
(d)..................................... (b).
(e)..................................... 173.34(c).
(f)..................................... 173.301(d).
(g) intro
(g)(1) thru (g) (3)..................... 173.301(g)(1) thru (g)(3).
(h)..................................... (g).
(i)
(j)..................................... (i).
(k)
(l)..................................... (j).
(m)
173.301a(a)............................... 173.301(e).
(b)..................................... (e)(1).
(c)..................................... (e)(2).
(d)..................................... (f) .
(e)..................................... 173.34(b).
173.301b
173.302(a)................................ 173.302(a)(4), (a)(5)(i)
thru (iii).
(b)..................................... 173.302(a)(4), (a)(5)(i)
thru (iii).
(c)..................................... 173.301(e).
(d)..................................... 173.301(f).
173.302a(a) intro......................... 173.302(a).
(a)(1).................................. (a)(1).
(a)(2).................................. (a)(2).
(a)(3).................................. (a)(4).
(a)(4).................................. (a)(3).
(a)(5).................................. (a)(4) - (5).
(b)..................................... (c).
(c)..................................... (f).
(d)..................................... (f).
(e)..................................... (d).
173.302b
173.304(a)................................ 173.304(a) intro, (a)(1).
(a)(1).................................. (a)(4).
(a)(2)
(a)(3)
(b)..................................... (b).
(c)..................................... (a) intro.
(d)..................................... (e).
(e)..................................... (f).
173.304a(a)............................... 173.304(a).
(c)..................................... (c).
(d)..................................... (d) .
(e)..................................... (h).
173.304b
173.315(p)................................ 173.301(d)(5).
180.201
180.203
180.205(a)
(b)..................................... 173.34 (e)(2).
(c) intro............................... (e)(1).
(c)(1).................................. (e)(1).
(c)(2)
(c)(3).................................. (c)(3).
(c)(4)
(d)
(e)..................................... (e)(17).
(f)..................................... (e)(3).
(g)..................................... (e)(4).
(h)..................................... (e)(5).
(i)..................................... (e)(6).
180.207
180.209(a)................................ 173.34(e) intro.
(b)..................................... (e)(16).
(c)..................................... (e)(9).
(d)..................................... (e)(10).
(e)..................................... (e)(11).
(f)..................................... (e)(12).
(g)..................................... (e)(13).
(h)..................................... (e)(14).
(i)..................................... (e)(18).
(j)..................................... (e)(19).
(k)
180.211................................... 173.34(g), (i) through (l).
180.213................................... 173.34(c), (e)(7).

[[Page 58468]]

180.215................................... 173.34(e)(2)(v), (e)(8),
(e)(13).
------------------------------------------------------------------------

XI. Summary of Regulatory Changes by Section

Part 107, Subpart I

Section 107.801-107.807

This new subpart would contain procedures whereby persons may seek
approval from the Associate Administrator to be a cylinder requalifer,
an independent inspection agency (IIA), or to have chemical tests or
analysis performed outside the United States for DOT specification
cylinders manufactured outside the United States. These requirements
are contained currently in Secs. 173.300a, 173.34(e) and 173.300b,
respectively. This new subpart would contain the specific requirements.
Current requirements in 49 CFR Subpart H of Part 107 would be
referenced for minimum content of an application, the RSPA office where
an application is to be filed, and the procedures that will be used to
process or terminate an application for approval.
The criteria permit the selection of any person or organization,
foreign as well as domestic, that is technically competent to perform
the prescribed functions and is free from undue influence by persons
involved with the fabrication, ownership or movement of the cylinders
that the applicant, if approved, would be called upon to evaluate and
certify. Under this proposal, RSPA would accept for transportation in
the United States foreign-made cylinders that are similar in
construction to the proposed DOT metric-marked cylinders. As part of
this policy, if the United States recognizes cylinders manufactured
outside the United States and approved by a third party inspector
approved by another government, then equal treatment is expected of
that government relative to cylinders manufactured in the United States
and approved by an IIA approved by DOT. Therefore, a foreign third-
party inspector, who certifies cylinders manufactured outside the
United States, must submit a statement from the competent authority of
the foreign government stating that similar authority is delegated to
manufacturers of metric-marked cylinders in the United States and that
no additional limitations are imposed.
Proposed Sec. 107.803 (current Sec. 173.300a) prescribes
application procedures for approval or renewal as an IIA. These
procedures, contained currently in Sec. 173.300a, would also permit an
IIA, upon approval by the Associate Administrator, to perform other
functions relating to the cylinder requalification requirements
prescribed in Part 180.
Proposed Sec. 107.805 (current Sec. 173.34(e)(2)) prescribes
application procedures for a person seeking an approval to perform
periodic cylinder requalifications. The procedures would be revised and
broadened to apply to any person who performs a function after which
the cylinder is required to be marked with a date as discussed in Part
IV of this preamble under the heading ``DOT approval of cylinder
requalifiers''. Because these provisions would be expanded to apply to
repairers and rebuilders, the terms ``retester'' and ``retester
identification number'' would be replaced with the terms
``requalifier'' and ``requalifier identification number,''
respectively.
Proposed Sec. 107.807 (current Sec. 173.300b) prescribes the
application procedures for issuance or renewal of an approval to
perform chemical analyses and tests outside the United States on DOT
specification cylinders manufactured outside the United States.

Part 171

Section 171.2

Paragraph (d)(3) would be amended to clarify that no one may mark a
requalifier identification number on a cylinder that has not been
requalified in accordance with the applicable requirements.

Section 171.7

This section would incorporate the latest editions of previously
approved CGA Pamphlets, incorporate certain additional ASTM and CGA
standards, and add references to certain publications of the American
National Standards Institute (ANSI).

Section 171.8

Definitions for ``metric-marked cylinder'' and ``nonmetric-marked
cylinder'' would be added.

Section 171.12

Paragraph (b)(15) would be revised to include references to
Sec. 171.12a(b)(13).

Section 171.12a

On August 18, 1998, RSPA issued a notice of proposed rulemaking
[Docket HM-215C; 63 FR 44312] which proposed to revise paragraph
(b)(13) to provide reciprocity for certain Canadian specification
cylinders to be transported within the United States. This HM-215C
proposed change is reprinted here for the benefit of readers.

Part 172

In the Sec. 172.101 Table, in column (8b) for the entries
``Cyanogen'', ``Germane'', and ``Iron Pentacarbonyl'' would be revised
to specify packaging authorization sections that are consistent with
their toxic properties.

Part 173

Section 173.34

The provisions in this section would be relocated to subpart I of
part 107, Sec. 173.301 and subpart B of part 180, as appropriate, and
Sec. 173.34 would be removed. All references to Sec. 173.34 in the HMR,
approximately 150 in number, would be removed and replaced with the
appropriate section reference.

Section 173.40

The requirements for toxic materials packaged in cylinders would be
revised to include an additional performance criteria for puncture
resistance. The requirements in Sec. 173.40 currently apply only to
materials in Hazard Zone A. All requirements except the controls on
closures would be expanded to Hazard Zone B materials. RSPA requests
comments on whether cylinders with Hazard Zone B materials should be
required to meet the same closure requirements required for Hazard Zone
A.
As discussed earlier in this preamble, DOT 3AL cylinders made of
aluminum alloy 6351-T6 are susceptible to sustained load cracking (SLC)
in the neck and shoulder area of the cylinder head and, therefore, may
leak in transportation. Leaks of Toxic Inhalation Hazard (TIH)
materials pose a significant threat to health and safety. At least two
major gas suppliers have voluntarily stopped using these cylinders in
TIH gas services. The proposed regulation will reduce the risk to
health and safety associated with TIH materials leaking through cracks
in cylinders. RSPA proposes that this regulation be imposed on the
effective date of this rule. After that date, cylinders made of 6351
alloy may not be filled and offered for transportation in TIH service.
Cylinders filled prior to that date may be offered for transportation
and transported to their ultimate destination and, when necessary,
cylinders containing unused gas may be returned to the person who
filled the cylinder.

Section 173.163

The requirements for nonmetric-marked cylinders containing hydrogen
fluoride would be amended to require ultrasonic examination as the only
authorized requalification method. This

[[Page 58469]]

proposal is based on the fact that the presence of moisture in a
cylinder containing hydrogen fluoride causes rapid corrosion of the
cylinder wall. Since removal of all moisture after hydrostatic testing
is very difficult, the current requirements authorize only the external
visual inspection in lieu of hydrostatic testing and internal visual
inspection. At the time the requirement was last amended, no other
alternative examination was available to reliably examine the cylinder
without introducing moisture into the cylinder. An ultrasonic
examination, to examine the internal sidewall for defects, can be
performed without introducing moisture to the cylinder. This section
also would be amended to include metric-marked cylinders for use in
hydrogen fluoride service.

Section 173.192

The title of this section would be revised to reflect that
requirements are applicable to Hazard Zone A gases. The restriction on
aluminum cylinders by highway and rail would be extended beyond arsine
and phosphine to include all Hazard Zone A gases. Paragraph (c) would
be amended to authorize alternative leakage tests having an equivalent
level of sensitivity as the current water bath leakage test, upon
written approval from the Associate Administrator. Currently without
exception, cylinders containing any amount of phosgene gas must be
subjected to a water bath leakage test prior to offering them for
transportation.

Section 173.198

An editorial change would be made to paragraph (a).

Section 173.226

Paragraph (a) would be revised to include only seamless
specification cylinders conforming to all requirements of Sec. 173.40.
Currently, Division 6.1, Hazard Zone A materials may be shipped in any
DOT specification cylinder except 8, 8AL and 39. RSPA believes that
this must be corrected in order to require these high hazard materials
to be transported in cylinders with a higher level of safety.

Section 173.227

Paragraph (a) would be revised to include only seamless and welded
specification cylinders conforming to the requirements of Sec. 173.40.

Section 173.228

Paragraph (a) would be amended to include metric-marked
specification cylinders and to require that cylinders used for bromine
pentafluoride and bromine trifluoride in Hazard Zones A and B materials
must conform to Sec. 173.40 as required for similar materials.

Sections 173.300a-173.300c

The provisions in these sections would be relocated to new Subpart
I of Part 107 and Secs. 173.300a, 173.300b and 173.300c would be
removed.

Sections 173.301-173.301b

Current Sec. 173.301 would be revised and proposed Secs. 173.301a
and 173.301b would be added. Section 173.301 would contain the general
shipper requirements for the use of specification cylinders that are
currently in Sec. 173.34 and the standard requirements for cylinders
that are currently in Sec. 173.301. These requirements include general
prefill requirements, maintenance and legibility of markings, PRD,
valve protection, manifolding of cylinders and the charging of foreign
cylinders. A derivation table showing the relocation of the
requirements appears in Part X of this preamble.
Certain other changes would be made to Sec. 173.301. The cargo tank
manifolding requirements that are currently in Sec. 173.301(d) would be
removed and placed with other cargo tank requirements in Sec. 173.315.
Proposed paragraph (a)(6) would prohibit the offering for
transportation and transportation in commerce of a filled cylinder
having a specified service life after its service life has expired.
This requirement will ensure cylinders that may be unsafe are removed
from service for transportation of hazardous materials.
Proposed paragraph (d) contains the general prohibition, that is
currently contained in paragraph (a), against filling a cylinder with
gases that are capable of combining chemically with each other or with
the cylinder material so as to endanger its serviceability. This
provision would be expanded to prohibit the use of DOT 3AL cylinders
made of aluminum alloy 6351-T6 for gases having pyrophoric properties.
Leaks of gases having pyrophoric properties, such as, silane, would
cause spontaneous flame and pose a significant threat to the health and
safety. A transition period of six months after the effective date of
the final rule would be provided for cylinders filled prior to the
specified date.
Proposed paragraph (f) contains PRD system and setting
requirements. The general purpose of a hazardous material packaging is
to prevent the unintentional release of a hazardous material under
normal conditions of transportation, including mishandling and minor
traffic accidents. Also, the packaging standards for cylinders are
designed to prevent failure of a cylinder from over pressurization,
particularly, when it retains substantial stored energy. Thus, a
balance must be set between competing interests for keeping a hazardous
material, particularly Division 2.1 and 2.3 gases and Division 2.2
gases with oxidizing properties, in a packaging and allowing such a
material to escape in order to prevent the packaging from rupturing.
Under current regulations, the type and setting of PRD systems are
established by CGA Pamphlet S-1.1. CGA Pamphlet S-1.1 allows a PRD
setting to be 75% to 100% of test pressure of the cylinder. Based on
RSPA's analysis of the currently authorized settings, a fully charged
nonmetric-marked DOT-3 series gas cylinder at 130 deg.F operating
temperature will likely release hazardous gases when the PRDs,
conforming to the authorized tolerances on device function, are set
below test pressure. RSPA believes this creates a serious threat to
safety by allowing an improper balance between keeping the hazardous
material in the package and preventing the cylinder from rupturing. In
contrast, RSPA does not believe this condition applies to DOT-4 series
cylinders because the ratio of test pressure to service pressure is 2:1
as compared to 1.67:1 for DOT-3 series cylinders.
To correct this condition, RSPA is proposing a PRD setting of 100%
of the marked test pressure for metric-marked and nonmetric-marked DOT-
3 series cylinders. To allow users sufficient time to change their
nonmetric-marked cylinders to meet the new PRD setting requirement,
RSPA is proposing that each cylinder be brought into compliance at the
first requalification of the cylinder after the effective date of the
final rule.
RSPA believes a setting of 100% of test pressure for a PRD is a
reasonable balance between keeping a gas in a cylinder and preventing a
cylinder from rupturing in the event of a fire or overfill. PRDs
designed to release at not less than test pressure will eliminate the
possibility of gas release through the relief device at a temperature
less than or equal to 54 deg.C (130 deg.F). At the same condition,
test pressure, the factor of safety for cylinder rupture is 1.6. As a
result of discussions with gas shippers, RSPA believes many major
shippers of DOT-3 series cylinders are currently setting PRDs at 90-
100% of test pressure for toxic and flammable gases. Because it is
common practice for many shippers of DOT-3 series cylinders to replace
the PRD at the time of a

[[Page 58470]]

cylinder's requalification, RSPA believes the proposal will result in
minimal incremental cost. For most gases, RSPA believes the increased
PRD setting will not significantly impact the performance of cylinders
in bonfire tests. RSPA requests the following:
1. Data on the performance of PRDs set at test pressure in bonfire
tests.
2. Comments on any gases or cylinders where a 100% of test pressure
setting could prevent a cylinder from passing a bonfire test.
3. Comments on the need to requalify PRDs in a bonfire test.
Proposed paragraph (h) would contain the cylinder valve protection
requirements that are currently in paragraph (g). These requirements
would be revised to require a performance-oriented approach to valve
assembly protection. A six foot drop test would be required to verify
that each cylinder valve (with or without protection assembly) has
sufficient strength to survive falls incidental to handling in
transportation. An acceptable drop test result would be that no leakage
occurs after the cylinder is dropped, although the cylinder may show
damage. A similar drop test is currently required for all non-bulk
performance-oriented packagings to ensure that the packages can
withstand normal conditions of transportation. RSPA believes that
cylinders should be held to at least the same level of performance as
drums and fiberboard boxes. A period of five years is proposed in
paragraph (h)(1)(i) to provide a smooth transition to meet this
performance requirement.
Proposed paragraph (k) would be added to permit foreign cylinders
to be imported into the United States and transported within a single
port area subject to certain conditions.
Proposed paragraph(m) would be added to prohibit cylinder
attachments with sharp features that may cause damage to other freight.
This new provision is in response to NTSB Recommendation I-92-001 with
respect to cylinders. Attachments for other hazardous material
packaging types will be addressed in a separate rulemaking action.
Proposed Sec. 173.301a would contain the current requirements
pertaining to the pressure in a nonmetric-marked cylinder at 70 deg.F
and 130 deg.F. It would also contain a grandfather provision that is
currently in Sec. 173.34(b).
Proposed Sec. 173.301b contains additional general requirements for
metric-marked cylinders used for nonliquefied (permanent) gases.
Definitions would be added for ``critical temperature,'' ``dissolved
gas,'' ``filling factor of liquefied compressed gas,'' ``high pressure
liquefied compressed gas,'' ``low pressure liquefied compressed gas,''
``permanent (non-liquefied compressed) gas,'' ``safety factor,'' and
``settled pressure.'' These proposed definitions, which are used in ISO
Standard 11622, will provide for harmonization with the international
standards.

Sections 173.302-173.302b

Current Sec. 173.302 would be revised and proposed Secs. 173.302a
and 173.302b would be added. Proposed Sec. 173.302 prescribes the
general requirements that would apply to filling a specification
cylinder with a nonliquefied (permanent) compressed gas.
Proposed 173.302a prescribes requirements for filling a nonmetric-
marked cylinder with a nonliquefied compressed gas, i.e., the current
requirements in Sec. 173.302. In addition, RSPA proposes to remove the
\5/6\ filling pressure limitation for DOT 3AL cylinders in carbon
monoxide service, in response to a CGA petition (P-1082). CGA furnished
information to support its conclusion that, although evidence shows
that carbon monoxide can cause stress corrosion cracking in steel
cylinders, there is no evidence that carbon monoxide causes corrosion
cracking or carbonyl formation in aluminum cylinders.
Proposed Sec. 173.302b prescribes requirements for filling a
metric-marked cylinder with permanent gas. Because a metric-marked
cylinder is stamped with the test pressure in bar, the fill pressure is
calculated from the marked test pressure. The charge pressure for a
metric-marked cylinder is \2/3\ of the test pressure for seamless DOT
3M, 3FM and 3ALM cylinders, and \1/2\ of the test pressure for welded
DOT 4M cylinders. The NPRM proposes a uniform standard which reduces
the possibility of overfilling and allows the gas industry to ship an
additional 1.5% gas. Because the NPRM proposes that the cylinder be
marked and charged in accordance with ISO Standard 11622, it would
facilitate shipments of hazardous material in DOT specification
cylinders internationally.

Section 173.304-173.304b

Current Sec. 173.304 would be revised and proposed Secs. 173.304a
and 173.304b would be added. Proposed Sec. 173.304 prescribes general
requirements that would apply to filling a specification cylinder with
a liquefied gas.
Proposed Sec. 173.304a prescribes specific requirements for filling
a nonmetric-marked cylinder with a liquefied gas, i.e., the
requirements that are currently in Sec. 173.304. Currently,
Sec. 173.304 limits the filling of a cylinder with a liquefied
compressed gas based on the maximum expected operating temperature (130
deg.F) and the minimum specific gravity of the liquid at 60 deg.F.
The maximum filling densities for many gases are prescribed in a table
that would be retained in the HMR in Sec. 173.304a for nonmetric-marked
cylinders.
The current regulation defines a liquefied compressed gas to be
partially liquid at an operating temperature of 20 deg.C (68 deg.F)
and authorizes a filling limit based on a wide range of critical
temperatures. Therefore, the safety factor derived from filling limits
is conservative for some gases and marginal for other gases. In
addition, the current regulations limit the internal volume of a DOT-39
specification cylinder to 75 cubic inches when used for liquefied
petroleum gases. This requirement is revised to apply to all liquefied
flammable gases and appears in proposed Sec. 173.304a(a)(3). In
proposed Sec. 173.304b for metric-marked cylinders, filling limits are
based on the maximum operating temperature and filling factor. Instead
of a maximum filling density table, the proposed filling limits are
based on a filling factor which is directly related to the critical
temperature of the liquefied compressed gas. The proposed filling
limits are applicable to all liquefied compressed gases. Under the
proposed filling limits, the filling factor is defined based on the
critical temperature and the operating condition of each individual
gas. Therefore, the proposal enhances the level of safety and allows
the gas industry to fill the cylinders with more product.

Section 173.334

This section would be amended to include metric-marked
specification cylinders.

Section 173.336

This section would be amended to include metric-marked
specification cylinders.

Section 173.337

This section would be amended to include metric-marked
specification cylinders.

Part 177

Sec. 177.840 Class 2 (Gases) Materials

RSPA proposes to revise paragraph (a)(1) to allow horizontal
loading of cylinders containing Class 2.2 materials. In addition, the
horizontal loading of Class 2.1 and Class 2.3 materials would be
permitted for cylinders designed so that the inlet to the PRD is
located in the

[[Page 58471]]

vapor space and provided that the cylinders are properly secured during
transportation.
This paragraph also would require the use of cylinder restraint
systems to reduce the likelihood of the cylinders being ejected from
the vehicle in event of an accident. This proposal is based on a NTSB
Recommendation I-90-008, that urges RSPA to require hazardous materials
packages to be secured with adequate cargo restraint systems to prevent
their ejection from the vehicle during transportation. NTSB made the
recommendation following an accident in Collier County, Florida that
involved a number of cylinders, containing a poisonous by inhalation
gas, being ejected from an overturned tractor-flatbed semitrailer.
Considering the wide variation in cylinder sizes, and the various types
of restraints that would be required, RSPA solicits information on
anticipated safety benefits and the costs of requiring the use of
restraint systems, particularly on small businesses.

Part 178

Section 178.46

As discussed in Part IX of this preamble, the tables in paragraph
(b)(4) would be revised to remove aluminum alloy 6351 as an authorized
material for the manufacture of DOT 3AL seamless cylinders. In
addition, in Table 1, several changes would be made to the chemical
composition limits for 6061 alloy for consistency with limits stated in
The Aluminum Association Standards and Data, 1993 edition. The Si
maximum that is currently stated as 0.80% would be revised to read
0.8%, the Fe maximum that is currently stated as 0.70% would be revised
to read 0.7%, the Mg minimum that is currently stated as 0.80% would be
revised to read 0.8%, and the Mg maximum that is currently stated as
1.20% would be revised to read 1.2%. Finally, Table 1 limits the
chemical composition of Pb (lead) and Bi(bismuth) to 0.01. RSPA
proposes to change these limits to 0.005.

Section 178.69

This new proposed section contains general design and manufacturing
requirements applicable to all metric-marked DOT specification
cylinders. This proposed section contains much of the same information
as the current Sec. 178.35, including compliance, inspection and
analyses, duties of inspector, PRDs, and markings; however, proposed
Sec. 178.69 is extended to address definitions, authorized material,
threads, and tests. Thus, Sec. 178.69 would simplify the regulations in
that all information common to metric-marked cylinders will be
centrally located, and will allow the simplification and streamlining
of the individual cylinder specifications proposed in Secs. 178.71,
178.72, 178.73 and 178.81.
Paragraph (b) will define common terms for clarity and consistency.
The addition of the new definition for ``volumetric expansion test''
will clarify RSPA's meaning of the many terms used by industry to
describe pressure testing.
Paragraph (c) specifies the requirements for inspection and
analyses. RSPA proposes that all DOT 4-series metric-marked cylinders
have inspection and analyses performed by an independent inspection
agency.
In paragraph (e), duties of the inspector, RSPA proposes a change
to allow the inspector to obtain a certified cast or heat analysis from
the cylinder manufacturer in addition to the material producer or
supplier, as needed. The current regulations require the inspector to
verify that the material of construction meets the requirements of the
applicable specification by either making a chemical analysis of each
heat of material; obtaining a certified chemical analysis from the
material manufacturer for each heat of material; or by making a check
analysis of a sample from each coil, sheet, or tube if an analysis is
not provided by the material manufacturer for each heat of material.
These alternative methods for verifying compliance are something raised
by independent inspectors to require cylinder manufacturers to perform
check analyses when readily available information may be used. The
proposed regulation would allow cylinder manufacturers to use analyses
obtained from the mill to verify the material conforms to standards for
the cylinder specification.
Paragraph (f) specifies performance-oriented requirements for
threads. These requirements would allow the manufacturer to design the
threads in conformance with any appropriate standard as long as certain
thread shear strength limits are met.
Paragraphs (h) and (i) list all tests that apply to metric-marked
cylinders. A new approach for the metric-marked cylinders is the
categorization of design qualification tests (paragraph (h) in addition
to production tests in paragraph (i)). These paragraphs include
criteria for each test as well as acceptance criteria. The individual
cylinder specifications prescribe which tests in Sec. 178.69 apply to
each specification, as well as any unique test requirements or
acceptable results. Centralizing all test information in one location
reduces repetition in the regulations and reduces the likelihood of
inconsistent requirements in the specifications. The requirement that
new metric-marked cylinders have cycle testing performed during design
qualification incorporates current industry practice. RSPA believes
that the cycle test is an important design performance test that
assesses cylinder fatigue life and, therefore also, proposes this
requirement for welded cylinders.
Paragraph (i)(12) contains requirements for ultrasonic examination
(UT); a non-destructive test method designed to detect surface and
subsurface flaws and to measure the thickness of a cylinder and the
size of a flaw or crack. The UT equipment has the capability to detect
the presence of discontinuities on or even within the cylinder
sidewall, shoulder, or bottom. UT would be required for all seamless
and some welded metric-marked cylinders at the time of manufacture.
Paragraph (k) prescribes marking requirements. A significant change
for the new metric-marked cylinders is marking with the test pressure,
rather than service pressure, expressed in bar. To communicate vital
information to requalifiers, metric-marked cylinders that require UT
examination during requalification must be marked ``UT'' as well as
with the minimum wall thickness. Other markings, such as country of
origin, will be required for metric-marked cylinders; thereby making
them more acceptable for transportation of hazardous materials in
international commerce.
Paragraph (l) includes a prohibition on coatings that may interfere
with inspections and tests, or that allow moisture to accumulate
between the cylinder wall and the coating. This provision is RSPA's
response to potential threats to safety associated with coating
materials, such as vinyl, which promote corrosion.

Section 178.70

This proposed section groups the common requirements that apply to
all DOT 3 series metric-marked seamless cylinders (DOT 3M, DOT 3ALM,
and DOT 3FM).
Paragraph (c) specifies materials for 3 series cylinders.
Authorized materials are located in Appendix A, Table 1 for steel and
nickel and Table 2 for aluminum. The steel compositions authorized
include two carbon manganese type, one chrome moly type steel, and one
stainless steel type. The aluminum composition is a 6061 alloy. These
compositions are broad enough to cover most material specifications
currently in use.

[[Page 58472]]

Paragraph (e) specifies wall thickness requirements. The current
DOT 3AAX requirement in Sec. 178.37(a)(2)(i) that adresses additional
design loads due to bending is proposed in this general section for all
DOT 3-series metric-marked cylinders. The inclusion of this requirement
sets a precedent in the HMR by allowing manufacturers the flexibility
to adapt any metric-marked cylinder specification to a ``tube trailer''
type cylinder.

Section 178.71

This section proposes the new DOT 3M metric-marked cylinder
specification. This specification combines aspects of the current DOT
3A, 3AX, 3AA, 3AAX, 3B, and 3BN specifications.
Proposed paragraph (c) authorizes construction using steel,
stainless steel, and nickel. The carbon manganese composition
authorized encompasses the steel currently used for DOT 3A
specification cylinders. The inclusion of the stainless steel
composition for a seamless cylinder will eliminate the need for many
exemptions.

Section 178.72

This section proposes the new DOT 3ALM metric cylinder
specification. This specification is very similar to the current DOT
3AL except that aluminum alloy 6351 is not authorized as a material of
construction.

Section 178.73

This section proposes the new DOT 3FM metric-marked cylinder
specification. The proposed DOT 3FM cylinder is designed to a high
stress level similar to the DOT 3T, and incorporates the strong
structural integrity of the DOT 3AA cylinder. This specification meets
many of the requirements of the ISO Standard 9809-2 cylinder, which
should make it readily acceptable in international commerce. The
authorized materials of construction are Grade B, a chrome molybdenum
type steel currently authorized for 3T cylinders and Grade E a new
chrome molybdenum type steel. Steels such as Grade E with higher
ultimate strength levels (above 115,000 psi) are currently authorized
under exemption. Because the most critical failure mode is cracking,
these cylinders will be subjected to UT examination at the time of
manufacture and requalification.

Section 178.81

This section contains specific requirements for the proposed DOT 4M
metric-marked cylinder specification. This specification combines
aspects of the current DOT 4B, 4BA, 4BW, 4B240ET, 4E, 4D, 4DA, 4DS and
4AA480 specifications. The maximum design test pressure is 140 bar
(2030 psi). This represents a pressure of more than double what is
currently authorized for welded cylinders, except the DOT 4DA and 4DS
specification, which have a maximum test pressure of 1800 psi.
Authorized materials would include aluminum alloy 5154 currently used
for the DOT 4E specification cylinder, as well as carbon, HSLA,
stainless, and 4130X steels. For DOT 4M specification cylinders with a
test pressure of 70 bar or more, the welds must be 100% radiographed to
provide assurance of the joint quality. Manufacturers of DOT 4M
specification cylinders would have the option of performing an
ultrasonic examination in lieu of the radiographic examination.
RSPA solicits comments on the need for a higher performance welded
cylinder specification than what is proposed in this NPRM. Comments are
also requested as to whether such a higher performance specification
should be distinguished from the lower performance by pressure, or by
material strength, or some other performance standard. RSPA is
currently considering a cylinder specification with a design test
pressure of either more than 140 bar (2030 psi) or with an ultimate
tensile strength of 830 Mpa (121,000 psi) or higher.

Part 180

Part 180, Subpart C

This new subpart would prescribe requirements for the continuing
qualification, maintenance, repair and rebuilding of DOT specification
and exemption cylinders. Most of the requirements are currently
contained in Secs. 173.34 and 173.301. Readers should refer to the
references under Part X of this preamble for the citation of the
corresponding provision that is similar to the current provision
contained in the HMR. The proposed requirements include DOT metric-
marked cylinders.

Section 180.203

This section contains definitions for terms used throughout Subpart
C. Some of these definitions are ``commercially free of corrosive
components,'' ``condemn,'' ``defect,'' ``rejected cylinder,'' and
``volumetric expansion test.''

Section 180.205

This section prescribes general requirements for the continuing
qualification and use of cylinders and for each person performing a
cylinder requalification function.

Section 180.207

This section prescribes requirements for the periodic
requalification of metric-marked specification cylinders. Proposed
Table I specifies the periodic requalification requirements. The
standard requalification period is once every five years, with extended
requalification periods provided for cylinders used exclusively to
transport certain gases. For example, when used exclusively for
noncorrosive, nontoxic (LC50 of not less than 5000 ppm) gases, DOT 3M,
3ALM, and 3FM specification cylinders must be requalified at least once
every ten years. Similarly, a DOT 4M specification cylinder must be
requalified at least once every 15 years. DOT 3M and 4M specification
cylinders used exclusively as fire extinguishers and meeting the
limitation of special provision 18 must be requalified at least once
every twelve years, as currently required for nonmetric-marked DOT
specification cylinders used as fire extinguishers.
All DOT 3M, 3ALM, 3FM and 4M specification cylinders must be
requalified using the ultrasonic examination, instead of a volumetric
expansion test. A DOT 4M specification cylinder, with a marked test
pressure of 70 bar or less and having a tensile strength less than 830
Kpa (120,000 psi), may be subjected to a volumetric expansion test in
lieu of an ultrasonic examination. Ultrasonic examination improves
safety by automating the identification and measurement of wall
thickness, pitting and cracking. It improves the probability of
detection for internal pits and cracks over current internal visual
inspection. Ultrasonic examination also reduces inspection and labor
costs, cleaning costs and waste water by allowing cylinder
requalification without removing the valve and purging the cylinder's
contents, and without the deliberate introduction of water into the
cylinder.
Comments are invited on the proposed requirements for ultrasonic
examination of cylinders. RSPA also solicits information on industry
practices in this area, the costs and benefits for using UT
examinations and the pass/fail criteria in Table II.

Section 180.209

This section prescribes requirements that are currently contained
in Sec. 173.34(e) for the periodic requalification of nonmetric-marked
specification cylinders. The current rule for the requalification of
most DOT specification and exemption cylinders requires a volumetric
expansion test, external and internal visual inspections

[[Page 58473]]

which are not suitable for detecting a buried or internal crack.
In proposed paragraph (a)(1), note 2 following the table requires
detection and measurement of the sidewall cracks in DOT 3T and 3HT
cylinders at each requalification period by an approved non-destructive
test (NDT) method. Cracks in these cylinders can be detected by using a
suitable NDT method, such as acoustic emissions or appropriate shear
wave ultrasonic examination. Because the ultimate tensile strength
(UTS) of DOT 3T and 3HT cylinders are above 7,900 Mpa (155,000 psi),
crack growth due to stress corrosion and fatigue can occur during
normal service. An undetected crack can grow to a critical size and
result in a catastrophic failure. Manufacturers of specificition DOT 3T
and other high strength exemption cylinders are required to perform UT
examinations at the time of manufacture.
Proposed paragraph (a)(2) allows for nonmetric-marked specification
cylinders to be ultrasonically examined as an alternative
requalification method. An external visual inspection is required to be
conducted in conjunction with the UT examination. The requalification
period for nonmetric-marked cylinders is the same as required in Table
I of this proposed section.

Section 180.211

This section prescribes repair, rebuild and heat treatment
requirements currently prescribed in Secs. 173.34(g) thru 173.34(l),
with certain revisions. These requirements are standardized and
simplified.

Section 180.213

This section contains marking requirements presently contained in
Sec. 173.34(e)(7), with certain revisions.
A new requirement for all specification cylinders would be added to
identify the type of inspection, test, or work performed on a cylinder.
This new requirement would enable shippers, carriers, and enforcement
personnel to readily determine the type and date of each inspection or
test, or whether any repair or rebuilding work has been performed on a
cylinder.
The methods for marking cylinders would permit stamping, engraving,
scribing or any other method approved in writing by the Associate
Administrator for HMS. In response to a NPGA petition, RSPA also
proposes allowing use of pressure sensitive labels to display the
requalification markings on fire extinguishers. However, RSPA is also
soliciting comments on whether there are any methods that should or
should not be authorized for application of requalification markings.
Currently, after a cylinder passes the requalification volumetric
expansion test, internal and external visual examinations, etc., the
RIN holder stamps the month and year of the test and its RIN on the
cylinder. This marking is normally accomplished with steel stamps.
However, RSPA has granted exemptions, such as E-11372, authorizing
certain fire extinguishers and fiber-wrapped cylinders to display the
requalification markings using labels. RSPA is considering whether to
incorporate new marking methods for DOT specification cylinders
following the requalification process.
RSPA requests comments on the feasibility, costs and benefits of
alternative marking methods, and whether affected persons believe there
is justification for RSPA to adopt alternative methods.

Section 180.215

This section contains the reporting and record retention
requirements currently prescribed in Sec. 173.34(e)(8), with certain
revisions.
The retester authorization record requirements in current
Sec. 173.34(e)(8)(i) would be revised to include all cylinder
requalifiers who inspect, test, repair, or rebuild cylinders. In
addition, proposed paragraph (d)(1) requires that records covering any
work involving welding or brazing repairs, or the building or reheat
treatment of cylinders must be retained by the cylinder requalifier for
15 years. The requalifier would be required to retain inspection and
test records until expiration of the inspection or requalification
period or until the cylinder is again requalified, whichever occurs
first. Records of any welding or brazing repair, rebuilding or reheat
treatment would be required to be retained for 15 years.

XII. Regulatory Analyses and Notices

A. Executive Order 12866 and DOT Regulatory Policies and Procedures

This proposed rule is considered a significant regulatory action
under section 3(f) of Executive Order 12866 and was reviewed by the
Office of Management and Budget. The rule is considered significant
under the Regulatory Policies and Procedures of the Department of
Transportation (44 FR 11034) because of public interest. A preliminary
regulatory evaluation is available for review in the docket.

B. Regulatory Flexibility Impact

General
The Regulatory Flexibility Act (5 U.S.C. 601 et seq.) requires an
agency to review regulations to assess their impact on small entities
unless the agency determines that a rule is not expected to have a
significant economic impact on a substantial number of small entities.
RSPA is unable, at this time, to certify that this proposed rule will
not have a significant impact on a substantial number of small
entities. RSPA has performed an Initial Regulatory Flexibility Analysis
(IRFA) of this proposed rule's potential impact on small entities, and
the assessment has been placed into the public docket for this
rulemaking. Written public comments that clarify the degree of
potential impacts on affected small entities are requested.
IRFA Summary
The Regulatory Flexibility Act is concerned with identifying the
economic impact of regulatory actions on small businesses and other
small entities. Unless alternative definitions have been established by
the agency in consultation with the Small Business Administration, the
definition of ``small business'' has the same meaning as under the
Small Business Act. As RSPA has established no special definition, the
agency employs thresholds published under criteria in 13 CFR 121.101,
e.g., 500 employees for cylinder manufacturers (SIC 3443--Fabricated
Plate Work (Boiler Shops) and SIC 3462 Iron and Steel Forgings).
Need for the proposed rule. As indicated throughout the preamble to
this proposed rule, current requirements for the manufacture, use, and
requalification of cylinders can be traced to standards first applied
in the early 1900's. The regulations were subsequently revised in a
piecemeal fashion, with adjustments being made to address particular
situations and problems on a case-by-case basis. This notice represents
RSPA's first comprehensive review of requirements pertaining to the
transportation of compressed gases in cylinders and spheres. This
action is being taken to: (1) Simplify requirements for the production
of new cylinders, (2) provide flexibility in the design, construction
processes and permitted use of cylinders, (3) adopt advanced
technological processes and procedures for cylinder manufacturing and
requalification, (4) achieve an increased level of safety through
simplification of the rules and regulations, (5) reduce the need to
issue, and renew, exemptions

[[Page 58474]]

that permit variances from detailed specifications concerning materials
of construction, design, and manufacturing processes, and (6)
facilitate international commerce in the transportation of compressed
gases.
Objectives and legal basis for the proposed rule. The intended
effect of this action is to reduce threats to health, safety and
property in the transportation of hazardous materials, particularly
flammable, toxic and other compressed gases. Federal hazardous
materials transportation law (49 U.S.C. 5101 et seq.) directs the
Secretary of Transportation to prescribe regulations for the safe
transportation of hazardous materials in intrastate, interstate and
foreign commerce. Section 5103(b) specifies that the regulations shall
apply to persons transporting hazardous materials in commerce; causing
hazardous materials to be transported in commerce; or manufacturing,
fabricating, marking, maintaining, reconditioning, repairing, or
testing a packaging or container that is represented, marked,
certified, or sold by such persons as qualified for use in transporting
hazardous material in commerce.
Identification of potentially affected small entities. 1.
Businesses likely to be most affected by this proposed rule are
manufacturers of specification DOT-3 and DOT-4 series cylinders (SIC
3443 and SIC 3462). Currently, RSPA estimates there are 40
manufacturers of specification DOT-3 and DOT-4 series cylinders. Of
that number, approximately 29 are ``small businesses'' under the Small
Business Act.
In the case of approximately eleven (11) manufacturers (five (5) of
whom are small businesses) of high-pressure (specification DOT-3
series) cylinders there should be little or no burden attributed to
requirements contained in this proposed rule, as many of these new
processes and technological innovations have already been adopted as
part of their own quality management program.
In addition to the above, there are another twenty-nine (29)
cylinder manufacturers (twenty-four (24) of whom are small businesses)
identified in RSPA's database of registered markings for packaging
manufacturers, and/or holders of exemptions that authorize the
manufacture, marking, and sale of cylinders that do not fully conform
to specifications for the DOT-3 and DOT-4 series. Eight (8) of these
cylinder manufacturers (including five (5) that meet the criterion of a
small business) are members of the Compressed Gas Association (CGA),
one of the primary initiators of petitions for rulemaking to revise the
HMR for greater consistency with regulations of the world's leading
industrial nations. It is RSPA's understanding that all CGA members
support proposed revisions contained in the CGA petitions. However,
that leaves another twenty-one (21) non-CGA-member cylinder
manufacturers, of which RSPA assumes at least 90% (approximately
nineteen (19)) meet the SBA criterion for a small business, that would
be affected by the proposed rule.
Some small entities may experience an adverse economic impact
attributed to the proposed rule's prohibition on the manufacture of
non-metric-marked specification DOT-3 and DOT-4 series cylinders after
a future date (five years from the effective date of a final rule).
Prior to that date, small entities would, at their own discretion, be
permitted to manufacture (1) non-metric-marked cylinders only, (2)
metric-marked cylinders only, or (3) a combination of non-metric-marked
cylinders and metric-marked cylinders. However, after the phase-out
date, these small entities may manufacture DOT-3 and DOT-4 cylinders
conforming to metric-marked specifications only.
RSPA anticipates that, upon review of these proposed requirements,
some small entities currently producing specification DOT-3 or DOT-4
series cylinders may determine that it is not economically feasible to
continue this line of products. For example, RSPA estimates the average
annual cost of the proposed requirement for an independent inspection
agency to observe cylinder manufacturing operations and processes at
$59,286 per facility. However, that average is calculated on the basis
of a wide range of costs for individual facilities that produce
specification DOT-4 series cylinders (e.g., $5,000 for an occasional
production run to $100,000 for a manufacturer that operates a dedicated
line). For manufacturers that produce a relatively large volume of
these cylinders the CGA estimates the additional cost of manufacturing
attributed to this provision will be an additional 10 cents per
cylinder. For a completed 20-pound propane cylinder that currently
sells for approximately $25 (retail price), RSPA expects that the added
expense would not be prohibitively costly to the manufacturer or to the
ultimate consumer.
RSPA understands that the production of specification DOT-3 and
DOT-4 cylinders by some manufacturers that are small businesses
oftentimes is but one of a wide-range of pressure vessels, or other
products, in the company's product line. Knowing the importance of
specification DOT-3 and DOT-4 series cylinders to the viability of
these small entities, is critical to RSPA's determination of whether
this rule may have a significant economic impact on a substantial
number of small manufacturing companies. Small entities are, therefore,
specifically invited to provide comments on the economic impact of the
proposed rule on their overall operations.
2. In addition to cylinder manufacturers, there are approximately
1,400 businesses currently engaged in the periodic requalification of
high-pressure cylinders. Here, also, RSPA conservatively estimates that
at least 90 percent of these requalifiers are small businesses. This
number includes businesses that manage large fleets of cylinders, such
as cylinders charged with propane to power forklift trucks, and for use
by retail customers through cylinder exchange programs. Still other
companies, generally thought to fall within SIC 7389 (business
services, not elsewhere classified), manage fleets of cylinders used in
(1) carbon dioxide service for carbonated soft drinks, (2) fire
extinguisher service, and (3) compressed air/oxygen breathing equipment
used in recreational diving operations, as well as by emergency
services personnel, like firefighters. All of these businesses are
currently approved to requalify cylinders through performance of the
hydrostatic pressure test.
The proposed rule would require each business to determine whether
it should: (1) upgrade test equipment from the hydrostatic type to
ultrasonic examination type to be able to service the older DOT
specification cylinders and the new metric-marked cylinders, or (2)
continue to maintain its currently installed hydrostatic test equipment
and service only the older DOT specification cylinders (estimated to
now number 300 million, a majority of which may be expected to remain
in service well into the next century) and the proposed DOT-4M metric-
marked cylinder that have a marked test pressure of 70 bar.
RSPA anticipates that some small entities currently performing
requalification functions by the hydrostatic pressure test method may
determine that investments in new ultrasonic test equipment (requiring
an investment currently estimated at $50-$80 thousand amortized over a
period of ten (10) years) may not be economically feasible, considering
the comparatively small number of metric-marked cylinders (vs. the
current size of the domestic fleet of approximately 300

[[Page 58475]]

million cylinders) that will be produced beginning perhaps as early as
1999, and first requiring periodic requalification in 2004. Currently,
five (5) of the eighteen (18) retester facilities currently performing
requalification of cylinders by ultrasonic examination, rather than by
hydrostatic pressure testing, under terms of special exemptions issued
by RSPA are thought to meet the criterion for a small business.
Although the ultrasonic examination method initially involves a
large capital investment, it offers cost savings for businesses that
own and/or use cylinders for the transportation of compressed gases. In
addition, ultrasonic examination provides (1) substantial benefits for
increased safety, (2) opportunities for reducing emissions of hazardous
materials to the environment, and (3) reduced contamination of
cylinders.
Commenters are specifically invited to provide additional
information with respect to this proposed requirement for ultrasonic
testing of metric-marked cylinders and its potential impact on small
entities. RSPA requests comments from affected small entities regarding
the potential adverse impact this proposed rule may have on their
cylinder requalification operations specifically, and the overall
viability of their enterprise should they determine it would be
economically prohibitive to continue to perform cylinder
requalification services.
3. Finally, there are literally hundreds of thousands of commercial
establishments that own and use cylinders manufactured to
specifications in the DOT-3 and DOT-4 series. Those business sectors
include agriculture; mining; construction; manufacturing;
transportation, communications, electric, gas and sanitary services;
wholesale trade; retail trade; services; and many other nonclassifiable
establishments. On the basis of a Small Business Administration
estimate that of the 24 million businesses located in the U.S. only
15,000 (.000625%) are large firms, RSPA concedes it is likely that over
99% of the businesses that make use of compressed gases in DOT
specification cylinders are small businesses. (Source: SBA Office of
Advocacy, Small Business Answer Card 1998).
RSPA believes the proposed rules will generally have a small
individual, though significant in the aggregate (i.e., $10 million
annually), positive benefit for all of these businesses by making the
metric-marked cylinders they buy or lease acceptable for trade and use
in worldwide commerce. In addition, those cylinders will be allowed to
be charged with a wider range of compressed gases and other materials,
and, in many cases, the period between periodic requalification will be
extended by several years, thereby resulting in cost savings attributed
to less frequent inspections. For example, in the case of a
specification DOT-3AL aluminum cylinder, the 5 year retest cycle would
be extended to 10 years for the specification DOT-3ALM. In time, there
may be as many as 1 million such cylinders in carbon dioxide service
for the carbonated beverage industry alone. A single retest of this
fleet of cylinders over a ten-year period vs. the current five-year
period, at an average cost of $10 per cylinder, i.e., $10 million,
would result in aggregate savings to the cylinder owners of $1 million
per year. In the very competitive soft-drink industry, RSPA believes
that the cost savings would be shared broadly.
To the extent that RSPA has failed to recognize potential impacts
on the general universe of small entities that own or use cylinders,
commenters are invited to identify those impacts and the magnitude of
their affect on small entities.
Reporting and recordkeeping requirements. This proposed rule
contains one new requirement for reporting and recordkeeping.
Specifically, persons who requalify cylinders by a visual inspection,
as currently authorized by Sec. 173.34(e)(13), would, under proposed
Sec. 180.209(g), be required to first obtain a requalification
identification number (RIN) from RSPA's Associate Administrator for
Hazardous Materials Safety under provisions of proposed Sec. 107.805.
Essential elements of the application for approval include: (1) the
name and address of the facility manager, (2) identification of the DOT
specification/exemption cylinders that will be inspected at the
facility, and (3) a signed and dated certification by the applicant
that the facility will operate in compliance with applicable
requirements of the HMR, and that the hazmat employees performing
inspections have been properly trained, to include familiarization with
the appropriate CGA C-6 series pamphlets concerning the conduct of
visual inspections.
An approval, if issued by the Associate Administrator for Hazardous
Materials Safety, would be effective for a maximum of five years, at
which time the approval holder would have to file a new application for
approval. Other than the requirements for having to file an application
for approval, and entering the four-digit RIN (in addition to the
month, year and letter ``E'' currently required) on each cylinder
requalified by the visual inspection method, there is no additional
regulatory burden associated with this proposal.
While the actual number of facilities currently operating under the
exception provided by Sec. 173.34(e)(13) is unknown, RSPA assumes, on
the basis of data compiled by the Bureau of the Census, that the actual
number is not more than 6,691, of which 5,651 are retail dealers of
bottled liquefied petroleum gases (SIC Code 5984), 968 are merchant
wholesalers of industrial gases, except liquefied petroleum gases (SIC
Code 5169), and 72 are entities identified as EPA-approved reclaimers
of refrigerant gases.
On a per facility basis, RSPA estimates the cost of this reporting
and recordkeeping requirement would be $122.50 per five-year cycle.
This estimate was calculated on the basis of cost data submitted by
RSPA to the Office of Management and Budget in support of an approval
issued by OMB (2137-0022) concerning Testing, Inspection and Marking
Requirements for Cylinders. RSPA does not see this proposed regulatory
requirement as inhibiting the ability of currently excepted retesters
to continue to provide this cylinder requalification service to an
extent that it threatens the viability of their primary business, i.e.,
the sale of compressed gases in relatively small units. RSPA
specifically invites commenters to provide data that supports or
refutes this estimate of the costs of compliance with the new
requirement to obtain a retester (requalification) identification
number and its impact on small businesses currently authorized to
perform this requalification function without first having to obtain an
approval from the Associate Administrator for Hazardous Materials
Safety.
Related Federal rules and regulations. With respect to the
production, permitted use, and periodic requalification of cylinders
used in the transportation in commerce of compressed gases, there are
no related rules and regulations issued by other departments or
agencies of the Federal government.
Alternate proposals for small businesses. The Regulatory
Flexibility Act directs agencies to establish exceptions and differing
compliance standards, when possible, for small business, while still
meeting objectives of the applicable regulatory statutes. In the case
of manufacture, use, inspection, testing, retesting and requalification
of DOT specification cylinders in compressed gas service, RSPA believes

[[Page 58476]]

that it is not possible to establish such differing standards and still
accomplish the objectives of Federal hazardous materials transportation
law (49 U.S.C. 5101-5127). RSPA further believes that the discussion in
this NPRM as to the need for regulatory action, issues raised by many
of the affected parties through petitions for rulemaking, applications
for exemption, and otherwise, effectively requires RSPA to apply one
set of requirements applicable to small and large businesses alike.
While certain regulatory actions may affect the competitive
situation of an industry by imposing relatively greater burdens on
small-scale than on large-scale enterprises, RSPA does not believe that
this will be the case with the proposed rule. The principal types of
compliance expenditure effectively required by the proposed rule would
be imposed on each cylinder represented through its specification
markings as conforming to a DOT specification, whether manufactured by,
used by, or serviced by a large or a small business. There are
administrative efficiency advantages, and economies of scale, available
to a large firm, but the requirements considered in this rulemaking are
intended to assure a minimum level of safety for packagings used to
contain hazardous materials that pose high-order risks in
transportation. Thus, no provisions may be waived simply on the basis
that they would be burdensome to a small business.
At the same time, RSPA notes that the proposed rules were developed
under the assumption that small businesses comprise an overwhelming
majority of entities that would be compelled to comply, particularly
regarding permitted use of cylinders and their periodic requalification
for continued use. For that reason, in its development of the proposed
rules, RSPA considered each requirement and determined this set
represents the minimal requirements necessary for it to be able to
assure an adequate level of safety in transportation.
For example, as an accommodation to small businesses, RSPA proposes
to (1) permit facilities to continue to use their currently installed
hydrostatic pressure test equipment to retest non-metric marked
specification cylinders, millions of which have been in service for
several decades and may be expected to continue in service for many
more decades, and (2) permit the requalification of certain metric-
marked cylinders, i.e., specification DOT-4M with a marked test
pressure 70 bar.
Section 610 Review
Pursuant to section 610 of the Regulatory Flexibility Act (5 U.S.C.
Sec. 610), RSPA has conducted a rev

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Source: Frix Law Library, https://www.frixlaw.com/law-library/documents/fr%3A98-28118. Public record. Not legal advice.