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
Numerous questions on lockout/tagout under 1910.147 and Subpart S. 1910.147
Determining work-relatedness for injury that occurred in company parking lot 1904 - Table of Contents, 1904.5(b)(2)
Applicability of 29 CFR 1910 standards to the oil and gas well drilling and servicing industry. 1910.5, 1910.5(c)
Training requirements under the HAZWOPER standard. 1910.120
Clarification of term "Active Hydrocarbon Zone" as it relates to the oil and gas well drilling operations; and the need to use FRC when performing drilling operations 1910.132, 1910.132(a), 1910.106, 1910.119
Region V request for enforcment guidance on portland cement and hexavalent chromium 1926.50, 1926.50(g), 1926.51, 1926.51(f)(1), 1926.95, 1926.1126, 1926.1126(g)(1), 1926.1126(h)(3)(i)
Applicablity of Subpart S to tunnels contructed by auger boring. 1926.800, 1926.800(a)(1)
Clarification of monitoring and sampling requirements for hexavalent chromium. 1910.1026, 1910.1026(d)(2), 1910.1026(j)
Whether OSHA will rely on ANSI Z359.1-2007, regarding snaphook compressive strength requirements, in enforcing the general duty clause with respect to personal fall arrest systems in construction, as announced in Letter #20070920-8088. 1926.502, 1926.502(d)(3), 1926.502(d)(4)
Clarification on most authoritative when multiple medical opinions are provided. 1904 - Table of Contents, 1904.6
Requirement for bloodborne pathogen training to be conducted during working hours. 1910.1030
Recording days away and/or restricted work activity when employee is able to work part of a shift. 1904 - Table of Contents, 1904.7
Clarification of the terms street clothing and work clothing as used in the asbestos standard for construction work. 1926.1101, 1926.1101(f), 1926.1101(f)(2), 1926.1101(i)(1), 1926.1101(j)(1), 1926.1101(j)(2)
Use of smoke escape hoods meeting the ANSI-ISEA standard 1910.134, 1910.134(c)(2), 1910.134(d)(2)(ii), 1910.134(k), 1910.134 App D
Acceptable equivalent to control lines for a Controlled Decking Zone (CDZ) in steel erection activities. 29 CFR 1926.760(c)(3). 1926.760, 1926.760(c)(3), 1926.502(f)(2)(iv)
Whether OSHA prohibits the use of a double D-bend elbow ("Rams Horn") shut-off valve at the end of a concrete pumping hose. 1926.702, 1926.702(e)
English language proficiency at construction sites. 1926.21(b)(2), 1926.503(a)(1)
Standards for decompression chambers for use with pressurized face-tunnel boring machines. 1926.803, 1926.803(e)(5), 1926.803(m)(3)
Hand-held gas-powered cut-off saws. 1926.303(d)
The definitions of combustible and flammable liquids under 29 CFR 1926 and 29 CFR 1910. 1910.106, 1910.106(a)(18), 1910.106(a)(19), 1926.155, 1926.155(c), 1926.155(h)