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
Hierarchy of air contaminant controls; respirators for emergencies. 1910.134(a)(1), 1910.134(d), 1910.38(a), 1910.120(q)(1), 1926.65(q)(1)
Training for plant maintenance personnel and HAZWOPER. 1910.120
Support zone personnel at a CERCLA thermal destruction site. 1910.120
Transportation of hazardous waste. 1910.120, 1910.120(q), 1910.1200, 1975.1
Evaluation of a "generic" Material Safety Data Sheet (MSDS) for copper/copper alloys. 1910.1200
The hazardous waste operations and emergency response regulation. 1910.38, 1910.120
OSHA's Hazard Communication Standard. 1910.1200
Clarification of training certification. 1910.120
OSHA's Hazard Communication Standard. 1910.1200
Guidance on whether "patch test kits" are exempt from the labeling requirements of HCS. 1910.1200
EPA CERCLA regulations and site monitoring requirements of 1910.120. 1910.120
Updated material safety data sheets. 1910.1200
Requirements of hazard communication standard for listing chemicals. 1910.1200(e)(1)(i)
Alarm systems for employee evacuation and/or response. 1910.38, 1910.165, 1910.120, 1910.1200
Background of standards. 1910.120, 1910.1030
The OSHA Hazard Communication Standard and how it applies in various industries. 1910.1200
Employee "Right to Know" chemical labeling. 1910.1200
Labeling and RCRA requirements and the HCS standard. 1910.1200
Training requirements for hospital personnel involved in an emergency response of a hazardous substance. 1910.120
Employees who work at hazardous waste sites who are not involved in cleanup. 1910.120, 1910.120(a)(1)(iii), 1910.120(e)