Archive Notice - OSHA Archive

NOTICE: This is an OSHA Archive Document, and may no longer represent OSHA Policy. It is presented here as historical content, for research and review purposes only.

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

July 2, 1993

Mr. George S. Kennedy, CSP
Director of Safety
National Utility Contractors Association
Suite 360
4301 N. Fairfax Drive
Arlington, Virginia 22203-1627

Dear Mr. Kennedy:

Thank you for your letter of April 7, to Art Buchanan, OSHA - General Industry Compliance Assistance. You made seven specific requests for interpretation regarding the Permit-Required Confined Space (PRCS) standard 1910.146. This response follows the question sequence which is reflected in your letter.

1. Paragraph (c)(5) of the standard addresses alternative procedures for working in permit-required confined spaces (permit spaces) which contain only actual or potential atmospheric hazards that can be controlled through the continuous application of mechanical ventilation alone. Paragraph (c)(7) is an option afforded employers who have permit spaces that can be reclassified as non-permit-required confined spaces because the identified hazards can be eliminated; that is, no on-going measures are needed to keep the space free of a hazard.

2. Fall protection must always be employed when there is a fall hazard. Specific fall protection requirements were not included in the PRCS standard because fall hazards are addressed by other existing standards.

3. Paragraph 1910.146(k)(3) does not prohibit an employer from fabricating a mechanical device for retrieval. Response 4 below provides additional guidance for the design and construction of mechanical devices.

4. Yes, the mechanical device used for emergency rescue must be designed and rated for human use. The standard specifies in paragraph 1910.146(k)(3)(ii) that the retrieval equipment must be designed for personnel. The performance-oriented nature of the standard allows flexibility as to the design specifications of the retrieval equipment itself. OSHA accepts certification by manufacturers as well as listing (as being tested) by Nationally Recognized Testing Laboratory (NRTL). An employer may design, manufacture, test, and certify (for example by a registered professional engineer) mechanical devices used for retrieval of personnel from a vertical space.

5. The use of a retrieval system is preferred for all entries to facilitate non-entry rescue. However, the standard does not require use of a retrieval system if the retrieval equipment would increase the overall risk related to permit space entry or would not contribute to the rescue of the entrant.

6. The standard does not require that an employer verify the training of outside rescue service members. However, paragraph [(k)(2)], which applies to all employers who have employees enter spaces to perform rescue, requires that rescue service employees be adequately trained. All employers, through their obligation under the Occupational Safety and Health Act, must assure that the protections afforded employees under the Act are maintained.

7. Attendants who perform non-entry rescue are not required by (k)(2) to be trained in basic first aid or CPR. However, under paragraph (d)(9) the employer must develop and implement procedures for providing necessary emergency services to rescued employees. Basic first-aid and CPR are considered to be part of necessary emergency services. Therefore, where non-entry rescue is utilized, the employer would either train the attendant or arrange to have trained personnel summoned to provide CPR or first aid for entrant.

[This document was edited on 02/15/99 to strike information that no longer reflects current OSHA policy.]

If you have further questions on these points please contact Art Buchanan or Don Kallstrom by telephoning (202) 219-8031.


Roger A. Clark, Director
Directorate of Compliance Programs

April 7, 1993

Mr. Art Buchanan
OSHA - General Industry
Compliance Assistance
200 Constitution Ave., N.W.
Washington, D.C.

Dear Mr. Buchanan:

In reference to our telephone conversation on April 5, 1993 I am submitting the following questions relating to the new "Permit Required Confined Space Rule - 1910.146."

1. There appears to be some confusion about spaces that do not require a the use of a permit and permit program, and spaces that are classified non-permit. According to section 1910.146(5)(i) the employer does not have to comply with paragraphs (d) through (f) and (h) through (k) if the employer can demonstrate that testing and ventilation can control the potential hazards within the space. We realize that there are details that must be taken into consideration under (5)(i) and (5)(ii) in order to arrive at this conclusion. Other than the note regarding eliminating the hazard, it appears that both situations addressed in section (5) and section (7) result in a non-permit space. What is the difference between complying under section (5) and reclassifying the space as a non-permit space section (7)?

2. When a worker enters into a confined space does he/she have to be protected by all arresters attached to a manufactured tripod or equivalent support having a capacity of 5400 pounds? Manufacturers are telling employers that fall protection such as retractable lifelines or equivalent must be used at all times, is this correct?

3. Can an employer build or fabricate a fall support and retrieval hoist and still comply with the standard? Manufacturers are telling employers that retrieval systems must be approved for human use, if this is true, approved by whom? Can an engineer design a system for fabrication in-house?

4. Do hoists have to be specifically designed and rated for human use? If yes, rated by whom? What are the minimum requirements for retrieval hoists? Some manufacturers are attaching boat winches that are originally stamped "Not for human use", then after attaching the cable to the hoist placing a plate over the original label stating "Approved for human use". Following this change they are charging 10 times the original price. OSHA should specify minimum requirements for hoists, tripods, rescue devices taking into consideration that employers, especially construction employers, may have the in-house capability of designing and fabricating equipment that can meet the requirements. As one construction manager put it to me, "we can handle loads that weigh 10 tons but they don't think we are capable of lifting a 150 pound man out of a hole".

5. If a worker is inspecting the inside of a 200 or 300 foot pipe line, does he have to be equipped with a 200 or 300 foot retrieval line?

6. When off site rescue service, such as fire department rescue teams, are designated by the employer for complying with section (k) is it the employer's responsibility to verify the fire department personnel have been adequately trained in confined space rescue? If yes, how would you suggest that the employer confirm that each member of the rescue squad has been trained?

7. Do attendants that are responsible for external rescue have to be trained in first aid and CPR?

Please send your response to me at 137 Ruhle Road, Ballston Spa, NY 12020. Thank you for your assistance.


George S. Kennedy, CSP
Director of Safety