The Washington State Department of Agriculture asked OSHA whether minimum risk pesticides, spray adjuvants, and commercial fertilizer products intended for agricultural or commercial use are subject to the labeling requirements of the Hazard Communication Standard.
OSHA explained that the HCS exempts pesticides, as defined under the Federal Insecticide, Fungicide, and Rodenticide Act (FIFRA), from HCS labeling when they comply with EPA labeling requirements (29 CFR 1910.1200(b)(5)(i)). Although EPA does not require registration of Section 25(b) minimum risk pesticides — products like citric acid, corn gluten, garlic, and mint oil — these still meet the definition of pesticides and remain subject to EPA labeling rules under 40 CFR 152.25(f)(3). So they are exempt from HCS labeling.
There is an important catch: the exemption covers labeling only. Safety data sheets must still be provided if the products are otherwise covered by the standard (29 CFR 1910.1200(g)).
For spray adjuvants and fertilizers, the answer depends on classification. Products that are pesticides under FIFRA and subject to EPA labeling are exempt from HCS labeling. Products that don't meet those criteria must comply with HCS labeling unless another exemption applies, such as the Consumer Product Safety Act exemption (29 CFR 1910.1200(b)(5)(v)).