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
Applicability of the Laboratory Standard; MSDS and labeling requirements. 1910.1450(a), 1910.1200(g), 1910.1200(f)(1)
Chemical suppliers must ensure downstream flow of hazard information (MSDSs). 1910.1200(g)
Hazard communication requirements for diatomaceous earth. 1910.1200(d), 1910.1200(f), 1910.1200(g)
Emergency response training necessary for hospital physicians/nurses that may treat contaminated patients. 1910.120(q)(6), 1910.120(q)(8)
Clarification of systems for electronic access to MSDSs 1910.1200(g)
Comparing medical evaluation requirements in the HAZWOPER, Respiratory protection, and Fire brigades standards. 1910.120(f), 1926.65(f), 1910.134(e), 1910.156(b)(2)
Hazard determination; labeling of solid materials. 1910.1200(d), 1910.1200(f)(2)
Format for Material Safety Data Sheets (MSDSs). 1910.1200, 1926.59
Reporting threshold for non-carcinogenic mixtures on MSDSs. 1910.1200(d)
Using the telephone to back-up eletronic access to MSDSs. 1910.1200(g)(8)
Definition of a mixture under the Hazard Communication standard. 1910.1200(c)
HAZWOPER refresher training and training documentation. 1910.120(e), 1910.120(e)(2), 1910.120(e)(8), 1926.65(e), 1926.65(e)(2), 1926.65(e)(8)
The HCS does not apply to food items in a retail establishment 1910.1200, 1926.59
Manufacturer and employer responsibilities when providing MSDSs electronically. 1910.1200, 1926.59
Carcinogen status of titanium dioxide relative to OSHA Standards 1910.1200
Material Safety Data Sheets (MSDSs). 1910.1200
Clarification of the requirements of the Hazardous Waste Operations and Emergency Response Standard 1910.120
Application of HAZWOPER. 1910.120
Access to employee exposure and medical records. 1910.120, 1910.1020
The requirements of paragraph (m) in the OSHA HAZWOPER Standard. 1910.120