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.

Filters


Date Title Standard Number
8-hour total weight average (TWA) permissible exposure limit (PEL). 1910.1000, 1910.1001, 1910.1017, 1910.1018, 1910.1025, 1910.1027, 1910.1028, 1910.1029, 1910.1043, 1910.1044, 1910.1045, 1910.1047, 1910.1048, 1910.1050, 1910.1051, 1910.1052
Letter of compliance for a ladder stand-off with handrails device. 1926.1053
The use of solvent aerosol for controlling exposure to asbestos during automotive brake repair. 1910.1001(f)(3)
The appropriate method for assessing hydrogen sulfide peak exposure levels 1910.1000
The Lockout/Tagout Standard. 1910.147
Interpretation of the Process Safety Management of Highly Hazardous Chemicals Standard. 1910.119, 1910.147
Fall Protection. 1926.502(k)
No scaffold shall be erected, moved, dismantled, or altered except under the supervision of competent persons. 1926.20, 1926.451
Fall Protection Standards. 1926.501(b)(5)
Ironworkers involved in steel erection activities must be protected from falls. 1926.501
Review of a new product, "The Safety Boot". 1926.500, 1926.501, 1926.502, 1926.503
OSHA's new fall protection standards for construction will prohibit use of safety belts with side dee rings as part of a personal fall arrest system 1926.500, 1926.501, 1926.502, 1926.503
Clarification of the Process Safety Management standard with regard to material and energy balances. 1910.119
Requesting OSHA to comment on the Scaffold Industry Association testing procedures to determine fall arrest tie-off locations. 1926 Subpart L
OSHA's New Fall Protection Standard for the Construction Industry. 1926.500, 1926.451(g), 1926.451(h)
Seat belts for excavators. 1926.602
Use of explosion proof certified equipment inside of pipes and manholes. 1910.146, 1910.307, 1926.651
Proposed standard for workplace exposure to tuberculosis.
Appropriateness of using Mag-1 Eyewear eyeglass holders with full facepiece respirators and self-contained breathing apparatus (SCBA). 1910.134, 1910.134(g)(1), 1910.134(g)(1)(i), 1910.134(g)(1)(i)(A), 1910.134(g)(1)(i)(B)
Comments concerning tying off on aerial lifts. 1926.556