Letters of Interpretation

Lapse in Appropriations

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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.

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How to Request a Letter of Interpretation

Date	Title	Standard Number
03/10/2004	Use of personal fall arrest systems at the edge of a well, pit, shaft, or similar excavation.	1926.501, 1926.501(b)(7)(ii)
03/10/2004	Fall protection is not required where there is no feasible means of providing it while working on vehicles or trailers.	1926.500, 1926.501(b)(1), 1926.95(a)
03/10/2004	Fall protection and controlled access zones for overhand bricklaying	1926.501(b)(9), 1926.502(g), 1926.502(g)(3), 1926.502(g)(2), 1926.501(b)(4)
03/10/2004	Use of caution tape or rope to barricade a crane's swing radius; guarding of lug connectors on portable welders	1926.550(a)(9), 1926.403(a), 1926.403(i)(2)(i)
03/10/2004	Height to base width ratio for mobile scaffolds with/without outriggers.	1926.451(c)(1), 1926.452(w)(6), 1926.452(w)(6)(ii), 1926.452(w)(6)(iii)
03/09/2004	Lock out/Tag out periodic inspection requirements.	1910.147, 1910.147(c)(6), 1910.147(c)(6)(i), 1910.147(c)(6)(i)(B), 1910.147(c)(6)(i)(C), 1910.147(c)(6)(i)(D), 1910.147(c)(7)(iii), 1910.147(c)(7)(iv)
03/09/2004	Requirements for reverse signal alarms for vehicles with obstructed views to the rear.	1910.269, 1910.269(p)(1)(ii)(A), 1910.269(p)(1)(ii)(B)
03/04/2004	Recording criteria for recordkeeping cases involving occupational hearing loss.	1904 - Table of Contents, 1904.10(b)(4), 1910.95(m)(2)
03/04/2004	Requirement and design of fire-resistant barriers for oxygen and fuel-gas cylinders.	1926.350, 1926.350(a)(10)
03/04/2004	Wire rope clips on suspension scaffolds; safety latches on large crane hooks; order of assembly for hanging scaffolds; and horizontal lifeline design.	1926.502(d)(8), 1926.502(b), 1926.251(c), 1926.760(d), 1926.502(d)(14), 1926.451(a), 1926.451(b), 1926.451(f), 1926.251(a)(4), 1926.451(d)(12), 1926.550(g)(4)(iv)(B), 1926.753(d), 1926.550(g), 1926.502(d)(15)
03/01/2004	Training for telecommunications employees must be "appropriate" for worksites and job tasks.	1910.268, 1910.268(c)(1), 1910.268(c)(2), 1910.268(c)(3)
03/01/2004	The predominant use of structural steel would not be considered "residential construction"	1926.501(b)(13), 1926.502(k)
02/26/2004	Portable ladders not extending 3 feet above upper landing must be secured.	1926.1053, 1926.1053(b)(1)
02/23/2004	Permissibility of attaching welding leads to an occupied aerial lift bucket and using an external lifeline to anchor fall arrest equipment.	1926.351(c)(6), 1926.453(b)(2)(xi), 1926.453(b)(2)(v), 1926.453(b)(2)(iii), 1926.453(b)(2)(vi)
02/23/2004	Identification, inspection, and marking of cranes when manufacturer-supplied identifications are unavailable.	1926.550, 1926.550(a), 1926.550(a)(5), 1926.550(a)(6), 1926.550(b)(2), 1926.550(c), 1926.550(d), 1926.550(e), 1926.550(f), 1926.32(f)
02/20/2004	Hard hats are not required where there is no exposure to head injuries.	1926.100, 1926.100(a)
02/19/2004	Inspection, testing, and operation requirements for Woltman PVE 5021S pile driving equipment.	1926.20, 1926.20(b)(2), 1926.31, 1926.550, 1926.550(a), 1926.550(a)(17), 1926.550(b), 1926.550(b)(2)
02/19/2004	Fall protection components from different manufacturers may be used together provided connecting parts are sized compatibly.	1926.502, 1926.502(d), 1926.502(d)(5), 1926.502(d)(6), 1926.502(e)(7), 1926.502(e)(8)
02/14/2004	Process operators' training requirements to take limited action in stopping an emergency release; role in an incident command system.	1910.120, 1910.120(q)(3)(i), 1910.120(q)(6)(ii), 1910.120(q)(6)(v)
02/13/2004	Minimum exposure for inclusion in the hearing conservation program (HCP); removal criteria.	1910.95, 1910.95(c)(1), 1910.95(m)

Lapse in Appropriations

Letters of Interpretation

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