Letters of Interpretation

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. Each 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.

These letters of interpretation and the standards they address may not apply to OSHA State Plans. State Plans are required to have standards and enforcement programs that are at least as effective as OSHA's and may have different or additional requirements. Please see OSHA-approved State Plans for more information.

NOTICE:

How to Request a Letter of Interpretation

Filters


Date Title Standard Number
Permit Required Confined Space 1910.146(b), 1910.146(c)(1), 1910.146(d)(3)(iii)
Retention of atmospheric monitoring records for a permit-required confined space 1910.146, 1910.146(d)(5), 1910.146(d)(14), 1910.146(e)(6), 1910.1020, 1910.1020(b)(1), 1910.1020(c)(5), 1910.1020(c)(13), 1910.1020(d)(1), 1910.1020(d)(1)(ii)
Confined Space Entry Permits 1910.146(d)
Application of OSHA standards when an employer is using the "Focused Electrode Leak Locator" (FELL) 1910.302, 1910.303, 1910.307(c)(1), 1910.307(c)(2), 1910.307(c)(3), 1910.399, 1910.146
Frequency of refresher training for first aid and CPR 1910.146(k)(2)(iii), 1910.151, 1910.151(b), 1910.266(i)(7), 1910.269(b)(1), 1910.410(a)(3), 1915.87, 1915.87(c)(5), 1926.50, 1926.50(c), 1926.951, 1926.968
Permit Required Confined Space Isolation 1910.146(b), 1926.1202
Definition of Confined Space, as it may apply to large product heating and aging furnaces 1910.146, 1910.25(c)(3)
Permit-Required Confined Space Entry Requirements For IDLH and Non-IDLH Spaces 1910.146(b), 1910.146(k)(1)(i), 1910.134, 1910.134(g)(3)
Centralized Monitoring for Permit-Required Confined Spaces 1910.146(c)(5), 1910.146(d), 1910.146(i)
Permit-Required Confined Space Rescue Retrieval Lines 1910.146(k)(3), 1910.146(k)(3)(i), 1910.146(k)(3)(ii)
Clarification of OSHA training requirements for basic first aid and cardiopulmonary resuscitation (CPR). 1910.151, 1910.146, 1910.266, 1910.269, 1910.410, 1926.950
Controlling Confined Space Hazards in Deep Tanks for Parts Cleaning 1910.146, 1910.147
Retrieval Lines Tied to Rescuers Entering a Confined Space 1910.146
Applicability of the PRCS standard to aircraft maintenance activities. 1910.146, 1910.146(c)(4), 1910.146(c)(9), 1910.146(d), 1910.146(d)(5)
Whether written programs may be kept solely in an electronic format. 1910.146(c)(4), 1910.1030(c)(1)(i), 1910.1030(c)(1)(iii), 1910.1200(e)(1), 1910.1200(e)(4)
Employer selection of local fire department as its off-site rescue service for compliance with 29 CFR 1910.146(k)(1). 1910.146, 1910.146(k)(1)
Determining whether an aircraft fuel tank is considered a confined space. 1910.146, 1910 Subpart Z
Whether reclassification is available for permit-required confined spaces with potentially hazardous atmospheres. 1910.146, 1910.146(c)(7), 1910.146(d)(3)
Use of feasible engineering/work practice controls for exposure to Cr(VI) for welding in confined spaces; housekeeping and disposal of large/bulky waste materials. 1910.146, 1910.1026, 1910.1026(a)(4), 1910.1026(b), 1910.1026(c), 1910.1026(f)(1), 1910.1026(j), 1910.1026(j)(3)(i), 1915.1026, 1926.1126
PRCS and LOTO requirements for accumulation of stored energy in steam pits 1910.146, 1910.147, 1910.147(d)(5)(ii)