The Occupational Safety and Health Administration (“OSHA”) published a Request for Information (“RFI”) on December 9, 2013 concerning possible changes to the Process Safety Management (“PSM”) program codified at 29 C.F.R. 1910.119. See 78 Fed. Reg. 73756 (Dec. 9, 2013). Likewise, the Environmental Protection Agency (“EPA”) published an RFI on July 31, 2014 relating to possible changes to the similar Risk Management Program (“RMP”) rules codified at 40 C.F.R. Part 68. See 79 Fed. Reg. 44604 (July 31, 2014). In lieu of making some changes through rulemaking, OSHA chose to revise older policies. On June 5, 2015, OSHA issued an interpretation letter that addresses the method of determining whether chemical in a mixture exceeded a threshold quality.

In response, the American Chemical Council and the National Association of Chemical Distributors filed suit challenging the policy. On July 7, 2016, OSHA and the parties settled the suit and agreed to a revised policy. On July 18, 2016, OSHA rescinded and replaced that policy with a modified policy.

Whereas the general policy did not substantially change, OSHA agreed that certain aqueous solutions were not covered by PSM. These include:

  1. Ammonia, Anhydrous (CAS 7664-41-7);
  2. Dimethylamine, Anhydrous (CAS 124-40-3);
  3. Hydrogen Cyanide, Anhydrous (CAS 74-90-8);
  4. Methylamine, Anhydrous (CAS 74-89-5);
  5. Hydrochloric Acid, Anhydrous/ Hydrogen Chloride (CAS 7647-01-0);
  6. Hydrofluoric Acid, Anhydrous/ Hydrogen Fluoride (CAS 7664-39-3).

Special emphasis was placed on the case of Hydrogen Chloride and Hydrogen Fluoride. Both were listed twice under the same CAS Number and Threshold Quantity. In settling the suit, OSHA agreed that these chemical were effectively only listed once in the anhydrous (without water) form. In addition, OSHA determined that that “aqueous mixtures of hydrogen bromide (at concentrations below 63%) and mixtures of alkylaluminum (at any concentration) will fall within the partial pressure exemption under all normal handling and storage conditions.”

Otherwise, OSHA’s proposed revisions to PSM are still pending and the EPA is evaluating comments from its proposed rule. Stay tuned for more developments.