OSHA requirements are set by statute, standards and regulations. Our interpretation letters explain these requirements and how they apply to particular circumstances, but they cannot create additional employer obligations. This letter constitutes OSHA's interpretation of the requirements discussed. Note that our enforcement guidance may be affected by changes to OSHA rules. Also, from time to time we update our guidance in response to new information. To keep apprised of such developments, you can consult OSHA's website at https://www.osha.gov.

April 12, 1996

BMW Constructors, Inc.
1740 West Michigan St.
PO Box 2210
Indianapolis, Indiana 46222-0210

Dear Sirs:

This is in response to your letter requesting clarification of the Occupational Safety and Health Administration's (OSHA) standards addressing the use of escape only, self-contained breathing apparatus (SCBA) in permit-required confined spaces.

The confined space standard, contained in 29 CFR 1910.146 does not prescribe specific respirators to be used when performing permit required confined space work; instead, respirator selection is determined through compliance with the respirator standards, 29 CFR 1910.134 and 29 CFR 1926.103. Therefore, SCBAs approved for escape may only be used for emergency egress and not for entry or routine work in confined spaces. Respirators required as part of an entry permit must be selected in accordance with the requirements established by either 29 CFR 1910.134 or 1926.103.

In response to your specific questions, the following is provided:

1.Some owners of permit-required confined spaces require that contractors carry ELSA-10 escape SCBA equipment for each worker upon entry into the confined space. These escape SCBAs are simply air bottles with a ten minute air supply connected to a plastic hood. These SCBAs are to be used for emergency egress only and the confined space is of a nature that would not normally require any respiratory protection for workers. Is the possession of this equipment required by the OSHA standards or is this merely a requirement of the confined space owner to suit his own prerogatives?

First, it is important to keep in mind that the host employer that "arranges to have employees of another employer (contractor) perform work that involves permit space entry" has obligations that are spelled out in §1910.146(c)(8) (host employers). Any additional requirements that the owner may place on you and your employees would be a contract matter between you and the owner.

Since the entering employees in the question you posed would be your employees, you would be considered their employer and it is you that must meet all of the requirements of the confined space standard with respect to them. Those requirements include .146(d)(9) (development and implementation of rescue procedures) and .146(d)(4)(viii) (providing rescue and emergency equipment). If escape-type SCBAs would be necessary for a rescue, then it would be your obligation under the standard to incorporate them in your rescue procedures and make sure that they are provided. Therefore, the answer to your question, "is the possession of this equipment required by the OSHA standards ...? " is yes if the nature of the circumstances would require that they be provided as part of your rescue procedures.

We cannot be more definitive than this because OSHA did not attempt in the standard to specify the equipment that would be needed for rescues and escapes in every type of permit-required confined space. Instead we have adopted a performance-type standard that requires each employer to determine what equipment would be necessary in the circumstances that they face in each instance.

We do note, though, that the rescue-type SCBA is not sufficient for routine entry or work in a permit space.

2.Are ELSA-10 SCBAs considered respirators under 29 CFR 1926.103? If so, would the requirements of physical examinations apply? If this were the case, would this imply physicals for all workers regardless of whether they normally use respirators in their job duties or not.

Yes, ELSA-10 SCBAs are respirators under 1926.103 (and 1910.134). The standards do not require physical examinations, however. They recommend determination of whether employees are physically able to perform the work and wear the respirators. They require the employer to have a local physician determine what health and physical conditions are pertinent.

[This document was edited on 8/12/99 to strike information that no longer reflects current OSHA policy.]

3.Since 29 CFR 1910.146 does not specifically apply to construction operations, would you provide some guidance on OSHA's procedures for determining the difference between construction and maintenance operations in relation to this standard, as well as ANSI Z-117-1?

29 CFR 1910.12(b) defines construction work as "work for construction, alteration, and/or repair, including painting and decorating." Generally speaking reconfiguration of space or installation of substantially new equipment is usually considered construction, whereas refurbishing of existing equipment and space is considered maintenance.

Maintenance operations are covered by general industry standards contained in 29 CFR 1910 and construction activities are covered by the construction standards contained in 29 CFR 1926. While paragraph (a), scope and application, of 29 CFR 1910.146 does not apply to construction activities, is does not exclude contractors from coverage when performing maintenance type operations in confined spaces.

Thus, if you are a contractor performing maintenance type activities for a host employer, compliance with 29 CFR 1910.146 is required. Some examples of maintenance operations would be:


  • The partial patching, total removal of existing lining and replacement, and installation of a new lining in a tank.



  • The relining of a furnace with new refractory.



  • Tuck pointing and individual brick replacement in a manhole.



  • Relining of a sewer line using a sleeve which is pushed through a section of the existing system.



  • Repainting, which is part of a scheduled program to maintain a system or prevent its deterioration.


For construction activities, hazards not addressed by §1926.21(b)(6) can be addressed by the general duty clause (Section 5(a)(1) of the Act) based on the requirements of the ANSI standard.

If we can be of any further assistance, please contact me or Mr. Dale Cavanaugh of my staff at (202) 219-8136. Sincerely,

Roy F. Gurnham, P.E., J.D.
Office of Construction Services