Safety Standards for Scaffolds Used in the Construction Industry

DEPARTMENT OF LABOR

Occupational Safety and Health Administration

29 CFR Part 1926

[Docket No. S-205B]

RIN 1218-AA40

Safety Standards for Scaffolds Used in the Construction Industry

AGENCY: Occupational Safety and Health Administration, U.S. Department

of Labor.

ACTION: Proposed rule; limited reopening of the rulemaking record.

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SUMMARY: The Occupational Safety and Health Administration (OSHA) is

reopening the record for the proposed revision of the regulation of

scaffolds used in construction (part 1926, subpart L) (51 FR 42680,

November 25, 1986). This reopening solicits additional information

regarding written comments which pointed out that the proposed

provisions for scaffold access did not explicitly cover scaffold

stairways (stair/towers) and which suggested criteria for inclusion in

the final rule. Through this notice, the Agency also requests input on

suggested regulatory language to address the use of chimney bracket

scaffolds and tank builders' scaffolds; incorporates the scaffold-

related materials from the record for the proposed general industry

standard for walking and working surfaces (part 1910, subpart D)

(Docket S-041, 55 FR 13360, April 10, 1990); and incorporates an August

1993 NIOSH report (titled Fatal Injuries to Workers in the United

States, 1980-1989: A Decade of Surveillance) on fatal injuries to

workers. The new information and evidence received as a result of this

action will be used by the Agency in developing its final rule for

scaffolds used in the construction industry.

DATES: Written comments on the materials incorporated through the

notice of reopening must be postmarked by March 18, 1994.

ADDRESSES: Comments are to be sent to the Docket Office, Docket No. S-

205B, U.S. Department of Labor, room N-2625, 200 Constitution Avenue,

NW., Washington, DC 20210.

FOR FURTHER INFORMATION CONTACT: Mr. James F. Foster, Occupational

Safety and Health Administration, U.S. Department of Labor, room N-

3647, 200 Constitution Avenue, NW., Washington, DC 20210. Telephone

(202) 219-8148.

SUPPLEMENTARY INFORMATION:

I. Background

A. Scaffold Stairways

On November 25, 1986, OSHA proposed to revise the scaffold

provisions of the construction standards (51 FR 42680). The proposal

consolidated and updated the requirements for scaffolds. The Agency

received 601 comments on the proposal and several hearing requests.

OSHA held informal public hearings regarding proposed subpart L on

March 22-23, 1988, with Administrative Law Judge Joel Williams

presiding. At the close of the hearings, Judge Williams set posthearing

comment periods which ended on May 9, 1988. On August 11, 1989, the

Administrative Law Judge certified the hearing record.

Two subpart L commenters (Exs. 2-367 and 2-368) stated:

After a review of the ``Access'' section [proposed

Sec. 1926.451(c)], it is noted that a reference to scaffold stair/

towers (access units) has been omitted from the proposed revisions.

The scaffold stair/towers are the most common and safest method of

obtaining access to scaffold units and should be included within

this Subpart.

In particular, one commenter (Ex. 2-368) suggested that OSHA insert

a new paragraph Sec. 1926.451(c)(5) as follows:

Scaffold stair/towers shall:

(i) Have inside and/or outside handrails;

(ii) Have landing platforms at every level, with a 19'' (48.3

cm) minimum width;

(iii) Have width of stair unit at a minimum of 19'' (48.3 cm)

between handrails; and

(iv) Have treads and landings of slip resistant surfaces.

Also, a commenter (Docket S-041, Ex. 3-414) on proposed part 1910

subpart D (Walking and Working Surfaces) stated:

As in the case of guardrails, the stair rails section is based

on the use of this product in permanently installed locations in

buildings or industrial structures. It does not consider stair rails

used in conjunction with scaffold applications.

Scaffold suppliers utilize step units which have been fabricated

specifically to be used as access to scaffold platforms. These step

units are manufactured with hand rails which are sold as a component

of these step units. The OSHA standard should state that these

fabricated step units are acceptable for scaffold access. This will

eliminate the confusion of the compliance officers in attempting to

enforce permanent stair rail standards for scaffold access

components.

The standard should also indicate that stair angles listed in

the OSHA Standard pertain to permanently installed stairs in

structures and are not intended for use in designing temporary

scaffold access components.

The failure to address scaffold stairways in proposed subpart L was

inadvertent. OSHA is considering including the above-mentioned criteria

for scaffold stairways, as well as a definition for that term, in

subpart L. OSHA notes that, although two commenters used the term

``stair/towers'', the Agency is using the term ``scaffold stairways''

in the belief that it more fully describes the equipment used. OSHA

also notes that these stairways are used as part of a scaffold. The

Agency solicits public comment in these areas.

The Agency believes that scaffold stairways present a serious fall

hazard. OSHA is considering what protection should be required for

employees who use such stairs. In particular, the Agency is considering

the following issues:

1. Whether the Agency should adopt the provisions suggested by

the commenters;

2. Whether the Agency should specify that scaffold stairways

must have handrails, stair rails, midrails, screens, mesh,

intermediate vertical members or equivalent intermediate structural

members;

3. Whether OSHA should set other provisions for scaffold

stairways;

4. What criteria OSHA should set for any equipment or procedures

that it requires in conjunction with the use of scaffold stairways;

and

5. Whether OSHA should allow scaffold stairways which comply

with the requirements of subpart L to be used for access to

structures other than scaffolds.

6. Whether OSHA should set a maximum and a minimum angle from

the horizontal for scaffold stairways covered by subpart L? If yes,

what should those angles be?

7. Whether OSHA should require that scaffold stairways have

riser heights and tread depths that are uniform within each flight

of stairs? If yes, should the maximum variation be \1/4\ inch (0.6

cm) as is required in Sec. 1926.1052(a)(3)?

In particular, the Agency is seeking input on the extent to which

requirements for scaffold stairways covered by subpart L should be

consistent with the general provisions for stairways found in existing

Sec. 1926.1052 or in proposed Secs. 1910.25 and 1910.28. For example,

Sec. 1926.1052(c)(3) requires that stair rail systems installed before

March 15, 1991, be no less than 30 inches (76.2 cm) high and that those

installed after March 15, 1991 be no less than 36 inches (91.4 cm)

high. In addition, proposed Sec. 1910.28(c)(2) requires that stair

rails and handrails installed before 60 days after the effective date

of the final rule be at least 30 inches (76.2 cm) high, that handrails

installed subsequently be 30 inches (76.2 cm) to 37 inches (94 cm)

high, and that stair rails installed subsequently be at least 36 inches

(91.4 cm) high. Also, proposed Sec. 1910.28(c) sets requirements for

the following:

--Finger clearance between handrails ((c)(3));

--Surfacing handrails and stair rail systems to prevent puncture

wounds, abrasion injuries or snagging of clothing ((c)(4));

--Limiting the dimensions of openings in a stair rail system to 19

inches (48.3 cm) ((c)(5));

--Handrails to have the shape and dimension necessary to provide a firm

handhold ((c)(6)); and

Preventing the ends of stair rail systems from presenting projection

hazards ((c)(7)).

In addition, OSHA is considering if the unprotected sides and edges

of landings for scaffold stairways covered by subpart L need to be

provided with guardrail systems that meet the requirements of proposed

subpart L alone, or whether those guardrails must also satisfy the

criteria of proposed subpart M (51 FR 42718, November 25, 1986).

B. Chimney Bracket Scaffolds

On March 29, 1993, OSHA (58 FR 16509) reopened the rulemaking

record for proposed subpart L for information and comments regarding

the fall hazards from work on chimney bracket scaffolds. Such scaffolds

are usually used on tall chimneys and similar structures in the course

of repairs, demolition and other construction operations. The scaffolds

are usually circular because the structures on which they are used

(such as some chimneys, stacks and tanks) are usually roughly

cylindrical in shape. However, since these scaffolds are also used on

structures that have other shapes (e.g., rectangular chimneys), the

scaffolds are not always circular.

OSHA expressed concern in the March 29 notice that proposed

Sec. 1926.451(e) might not adequately address fall hazards on chimney

bracket scaffolds and requested responses to 17 questions regarding the

use of those scaffolds. On May 26, 1993, the Agency (58 FR 30131)

extended the comment period until June 28, 1993.

Based on a comment (Ex. 34-33) received from the National Chimney &

Cooling Tower Construction Safety and Health Advisory Committee, OSHA

is considering the following language for inclusion in the final rule

for subpart L:

(a) Brackets shall be secured in place by at least one wire rope

at least 1\1/2\ inch (1.3 cm) in diameter.

(b) A turnbuckle at least 1 inch (2.5 cm) in diameter shall be

used to tension the securing wire rope.

(c) The scaffold, each of its components (except wire ropes) and

the supporting structure shall meet the minimum strength

requirements of proposed Sec. 1926.451(a)(1) [four times the maximum

intended load].

(d) Each wire rope shall be capable of supporting, without

failure, at least 6 times the maximum intended load applied or

transmitted to that rope.

(e) Platform units shall be secured to the brackets.

(f) Platform units shall extend at least 12 inches (30.5 cm)

beyond each bracket.

(g) The span of platform units from bracket to bracket shall not

exceed 5 feet (1.52 m) on the outside of the brackets.

(h) Guardrail systems meeting the requirements of

Sec. 1926.451(e)(4) shall be provided.

(i) The supporting structure shall be inspected by a competent

person before scaffold erection begins.

(j) Materials shall not be dropped to the outside of the

structure.

(k) The scaffold shall be placed around the structure in only

one direction.

(l) A wire rope at least \5/16\ inches (0.8 cm) in diameter

shall be placed around the structure for employees erecting or

dismantling scaffolds so that the wire rope provides a safe

anchorage for each affected employee's personal fall arrest system.

In addition, the Agency is considering if it is appropriate to

require that employees working on chimney bracket scaffolds be

protected from fall hazards both by a ``Type I'' guardrail, as would be

required by proposed Sec. 1926.451(e)(4), and by a personal fall arrest

system. Also, OSHA is considering what provisions must be made for

rescue of employees from chimney bracket scaffolds in the event of

scaffold collapse or a medical emergency.

The Agency is also developing criteria for employers who would need

to comply with these provisions. For example, OSHA is considering the

following issues:

1. How would wire rope or other equipment be placed on a

chimney, stack, tank or other structure to provide a safe anchorage

point? Would compliance with the pertinent requirements of

Sec. 1910.66 appendix C be appropriate?

2. Is regulatory language other than that in proposed

Sec. 1926.451(f), Falling object protection, needed to address the

hazards of materials dropping to the outside of a chimney structure;

3. What criteria should a competent person apply when inspecting

a supporting structure prior to scaffold erection; and

4. How should employers secure platform units to the brackets so

that they do not inadvertently detach?

5. Should OSHA set criteria (such as dimensions and materials

used) for brackets used with chimney bracket scaffolds? What should

those criteria be?

6. Should OSHA require a positive locking device on the

bracket's hook that is placed over the wire rope? Would a positive

locking device prevent the unintentional separation of the hook from

the wire rope?

7. Should OSHA require that a ``shoe'' be placed on the bottom

of the brackets at the contact point with the structure? Would a

``shoe'' reduce the possibility of lateral movement of the brackets?

8. Should OSHA require that a proper size thimble be used to

connect the turnbuckle to the other end of rope?

9. Should OSHA specify a factor of safety of 4:1 for the

horizontal wire ropes used with chimney bracket scaffolds as

recommended by the only commenter (Ex. 34-33), or should the factor

of safety be set at 6:1 as the Agency specifies elsewhere when wire

ropes are used with scaffolds? OSHA is concerned that 4:1 factor of

safety might be inadequate given the reduction in strength that

occurs when wire rope clips are used as fasteners, and has placed a

6:1 factor of safety in paragraph (d) of the language set forth

above for consideration.

10. How would the employer protect the wire ropes used to secure

the scaffold and to provide anchorage for personal fall arrest

systems from abrasion or other damage due to contact with the

structure or scaffold?

11. Should OSHA specify that each platform unit on chimney

bracket scaffolds extend at least 12 inches (30.5 cm) over its

supports as recommended by the commenter, or at least 6 inches (15.2

cm) unless cleated or otherwise restrained as would be required by

proposed Sec. 1926.451(b)(6)?

The National Chimney & Cooling Tower Construction Safety and Health

Advisory Committee (Ex. 34-33) stated that the brackets could be

secured to a metal tank by welding rather than by use of a wire rope.

OSHA notes that both existing (Sec. 1926.451(m)) and proposed

(Sec. 1926.452(g)) subpart L regulate a similar type of scaffold, the

carpenters' bracket scaffold. In addition, American National Standards

Institute (ANSI) consensus standard, ANSI A10.8-1988 (Scaffolding

Safety Requirements for Construction and Demolition Operations),

already addresses carpenters' bracket scaffolds, but not chimney

bracket scaffolds. Accordingly, the Agency is considering if the

proposed requirements for carpenters' bracket scaffolds or the

pertinent provisions of ANSI A10.8-1988 would provide appropriate

guidance for employers using chimney bracket scaffolds when the

brackets are secured by welding.

OSHA is concerned that the use of U-bolt wire rope clips as wire

rope fasteners on the horizontal support ropes could result in damage

to the dead end of a rope. As the rope is lowered, the live end must

become longer due the increase in the circumference of the structure.

In order to accomplish this, the dead end gradually becomes part of the

live end. If the segment of the dead end that has become part of the

live end has been damaged by the U-bolt wire rope clips, the ability of

the rope to support the loads imposed on it may have been significantly

reduced. OSHA is concerned that in this case the rope might fail. OSHA

notes that there are other means of fastening wire ropes, such as

double-saddle clips, that will not damage the dead end of the rope.

Should OSHA prohibit the use of U-bolt wire rope clips on the

horizontal support ropes of a chimney bracket scaffold?

The Agency solicits comments and suggestions, with supporting

information, regarding the criteria needed for safe use of chimney

bracket scaffolds.

In addition, OSHA is considering the following term and definition

for inclusion in the final rule:

``Chimney bracket scaffold'' means a supported scaffold

consisting of a platform supported by brackets which are secured in

place around the circumference or perimeter of a chimney, stack,

tank or other structure by one or more wire ropes placed in an

approximately horizontal plane and tensioned by a turnbuckle.

The Agency requests comments on and any suggested changes to the

above-mentioned term and definition.

C. Tank Builder's Scaffold

Two commenters (Exs. 34-41 and 34-42) who responded to the March

29, 1993, reopening of the record of subpart L (58 FR 16509) stated

that OSHA should address tank builders' scaffolds in the final rule,

and noted that on April 4, 1975, the Agency granted users of tank

builder's scaffolds a permanent variance (40 FR 15139) from the

requirements of existing Secs. 1926.451(a)(4) (requiring guardrails and

toeboards), (a)(5) (setting criteria for guardrails and toeboards) ,

and (a)(10) (setting criteria for scaffold planking). OSHA found that

compliance with the provisions of the variance would provide employee

protection equivalent to that attained through compliance with existing

subpart L.

In light of that variance, OSHA is concerned that tank builders'

scaffolds may need to be addressed specifically in the final rule. OSHA

notes that both existing (Sec. 1926.451(m)) and proposed

(Sec. 1926.452(g)) subpart L regulate a similar type of scaffold, the

carpenters' bracket scaffold. In addition, ANSI A10.8-1988 (Scaffolding

Safety Requirements for Construction and Demolition Operations) already

addresses carpenters' bracket scaffolds, but not tank builders'

scaffolds. Accordingly, the Agency is considering if the proposed

requirements for carpenters' bracket scaffolds would provide

appropriate guidance for employers using tank builders' scaffolds. OSHA

solicits comments and suggestions, with supporting information, on this

issue.

Based on the requirements of the above-mentioned permanent variance

and proposed subpart L, OSHA is considering the following term and

definition for inclusion in the final rule:

``Tank builder's scaffold'' means a supported scaffold

consisting of a platform supported by brackets welded to the steel

plates used to construct a tank.

The April 4, 1975, variance provided for the use of scaffolds in

tank-building as follows:

(a) Loose tools and equipment shall be kept in well-designed tool

containers. This does not include fit-up bar, key plates, key channels,

or long handled maul which may be placed on the scaffold plank during

the time they are required for work. The loose tool containers shall be

secured to prevent their upset or dislodgement from the scaffold area.

(b) Areas beneath and far enough away from the base of the scaffold

to contain anything that falls from above shall be roped off and posted

with clearly visible signs stating: ``Danger Overhead Work.''

(c) A taut wire rope supported on the scaffold brackets shall be

installed at the scaffold plank level between the innermost edge of the

scaffold platform and the curved plate structure of the tank shell to

serve as a safety line in lieu of an inner guardrail assembly. In the

event the open space on either side of the rope exceeds 12 inches (30.5

cm), a second wire rope appropriately placed, or guardrails in

accordance with [existing] Sec. 1926.451(a)(5), shall be installed.

(d) Not more than three employees shall be working on a 10'6'' span

of scaffold planking at any one time.

(e) The maximum distance between brackets to which scaffolding and

guardrail supports are attached shall be 10'6''. These brackets shall

be welded to the steel plates.

(f) Scaffold planks of rough full-dimensioned 2'' (5.1 cm) x 12''

(30.5 cm) x 12' (3.66 m) Douglas Fir or Southern Yellow Pine of

Select Structural Grade shall be used. Douglas Fir planks shall have a

fiber stress of at least 1900 lb/in\2\ (130,929 n/cm\2\) and a modulus

of elasticity of at least 1,900,000 lb/in\2\ (130,929,000 n/cm\2\),

while Yellow Pine planks shall have a fiber stress of at least 2500 lb/

in\2\ (172,275 n/cm\2\) and a modulus of elasticity of at least

2,000,000 lb/in\2\ (137,820,000 n/cm\2\).

(g) All planking shall be secured from movement or overlapped in

accordance with [existing] Sec. 1926.451(a)(12).

(h) Guardrails shall be constructed of taut wire rope, and shall be

supported by angle irons attached to brackets welded to the steel

plates. These guardrails shall be at least of equivalent strength,

stability and height as those required for the 8 foot (2.44 m) span of

2'' (5.1 cm) x 4'' (10.2 cm) wood rails by [existing] 29 CFR

1926.451(a)(5). Guardrail supports shall be located at no greater than

10'6'' (3.20 cm) intervals.

OSHA seeks comments on the requirements of the April 4, 1975,

variance and on the following issues:

1. To what extent does the April 4, 1975, variance order

adequately address the hazards to which employees are exposed while

working from, under, or near scaffolds during tank-building

operations?

2. Are the requirements set out in Items (a), (b), (d), (e),

(f), (g), and (h) of the April 4, 1975, variance order adequately

covered by the general rules found in proposed subpart L.

3. OSHA is concerned that compliance with Item (c) of the April

4, 1975, variance might conflict with proposed paragraph

Sec. 1926.451(b)(4) which would require that the front edge of

platforms be positioned not more than 14 inches (35.6 cm) from the

face of the structure worked on, unless Type I guardrails are

erected along the open edge or body belt/harness systems are used to

protect employees from falling. In particular, OSHA is considering:

(a) To what extent would the taut wire rope placed at the

platform level between the innermost edge of the platform and the

curved plate structure of the tank provide protection equivalent to

that which would be required by proposed Sec. 1926.451(b)(4)?

(b) Are employees exposed to hazards when a wire rope is used in

this fashion? If so, what are those hazards and how can employees be

protected from them?

(c) Should the maximum space between the platform and the wire

rope be 12 inches (30.5 cm) as specified in the variance, or some

other distance? Should the maximum space between the wire rope and

the curved plate structure of the tank be 12 inches (30.5 cm) as

specified in the variance, or some other distance?

(d) What is the greatest distance that the brackets can be apart

without creating a space greater than 12 inches (30.5 cm)? What is

the greatest distance that the brackets can be apart without

creating a space greater than 14 inches (35.6 cm)? What, if any,

feasibility problems would arise from the selection of one distance

or the other?

(e) Are there any feasible means, other than installing a taut

wire rope, to reduce the space between the scaffold and structure?

(f) Should OSHA specify a minimum diameter for the wire rope? If

so, what should that diameter be?

4. If OSHA places provisions for tank builder's scaffolds in

non-mandatory Appendix A, should those provisions be consistent with

the provisions of the April 4, 1975, variance or with the proposed

provisions of Appendix A?

5. Are there any hazards associated with use of tank builders'

scaffolds that are not addressed by either the April 4, 1975,

variance or by proposed subpart L?

6. Are there any provisions of proposed Sec. 1926.451 which

should not apply to tank builders' scaffolds?

D. NIOSH Study of Construction-related Fatalities.

In August 1993, NIOSH issued a study of construction-related

fatalities titled Fatal Injuries to Workers in the United States, 1980-

1989: A Decade of Surveillance. The Agency believes, given the passage

of time since OSHA gathered information to draft the Preliminary

Regulatory Impact Assessment for proposed subpart L, the NIOSH study

will help the Agency assess the workplace hazards addressed by subpart

L. Therefore, OSHA has decided that this new information should be

incorporated into the rulemaking record as Exhibit 40 and that the

public should have an opportunity to comment on that information.

E. Incorporation of Docket S-041 (Part 1910, Subpart D) Materials

Related to Scaffolds

On April 10, 1990, the Agency proposed to update the requirements

for protection of employees on walking and working surfaces (part 1910,

subpart D, 55 FR 13360). The proposed general industry requirements for

scaffolds were generally consistent with those proposed for

construction. Proposed Secs. 1910.25, Stairs; 1910.28, Fall Protection

Systems; and 1910.30, Scaffolds generated public input which is being

considered as OSHA drafts the final rule for scaffolds covered by

subpart D. Some of those materials contain relevant information or

raise scaffold-related concerns not addressed in the comments on

proposed subpart L. The Agency believes that, in developing separate

standards for general industry (part 1910) and for the construction

industry (part 1926), the substance of those standards should be

consistent, where appropriate. Therefore, OSHA has determined that the

Agency needs to consider the scaffold-related information generated in

the subpart D rulemaking when the Agency drafts the final rule for

scaffolds in the construction industry. To this end, the Agency is

incorporating the pertinent exhibits from the general industry

rulemaking record (Docket S-041) into the record for the part 1926,

subpart L rulemaking (Docket S-205B). The incorporated materials will

be identified in the subpart L docket as Exhibit 41, with attachments.

II. Public Participation

Comments

Written comments regarding the materials incorporated into the

subpart L record through this notice must be postmarked by March 18,

1994. Four copies of these comments must be submitted to the Docket

Office, Docket No. S-205B, U.S. Department of Labor, room N-2625, 200

Constitution Avenue, NW., Washington, DC 20210. (202) 219-7894. All

materials submitted will be available for inspection and copying at the

above address. Materials previously submitted to the Docket for this

rulemaking need not be resubmitted.

III. Authority

This document was prepared under the direction of Joseph A. Dear,

Assistant Secretary of Labor for Occupational Safety and Health, U.S.

Department of Labor, 200 Constitution Avenue, NW., Washington, DC

20210.

It is issued under section 6(b) of the Occupational Safety and

Health Act (29 U.S.C. 655), and 29 CFR part 1911.

Signed at Washington, DC, this 26th day of January, 1994.

Joseph A. Dear,

Assistant Secretary of Labor.

[FR Doc. 94-2136 Filed 1-31-94; 8:45 am]

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