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. This 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. To keep apprised of such developments, you can consult OSHA's website at https://www.osha.gov.

January 24, 1983

Regional Administrator
Field Coordinator
Director, Federal Compliance and State Programs
SUBJECT: Thiram Standards in Washington and Oregon

As you are aware, approval of the Oregon Thiram standard was published December 11, 1979, and the Washington Thiram standard approval notice is in the National Office pending publication. We have recently become aware of several implications of State regulations of pesticides, which specifically relate to the Washington and Oregon standards on Thiram and should be discussed with those States. Please accept my apology for not surfacing these concerns earlier.

EPA, under the Federal Insecticide, Fungicide and Rodenticide Act (FIFRA), covers application and reentry aspects of Thiram, as well as other pesticides. (EPA can delegate enforcement of FIFRA to States in a similar fashion as OSHA's State programs. EPA has such agreements with Oregon and Washington agriculture departments.)

Section 4(b)(1) of the Act precludes OSHA regulation of Thiram, as well as other pesticides, except during manufacturing processes. Therefore, the following questions should be raised with Washington and Oregon prior to publishing the approval notice for the Washington standard.

-  Are WISHA and APD aware of EPA's responsibility for regulating Thiram, and that EPA delegated that responsibility to their States' EPA agriculture departments?

-  Have they intentionally chosen to exercise their authority beyond that of Federal OSHA, since 4(b)(1) precludes OSHA enforcement in that area?

-  Does State law permit them to exercise this additional authority?

-  Have the States coordinated their enforcement with the State agriculture departments?

-  Do the States standards overlap or conflict with the EPA/State requirements?

Please contact us if you would like additional explanation.