For decades, employers with cyanide exposure risk relied on a 1988 OSHA memo that said amyl nitrite required a physician's prescription and was the medically accepted initial response to cyanide poisoning. In this March 31, 2020 memo to Regional Administrators and State Plan Designees, OSHA formally updated that outdated guidance.
OSHA explained that amyl nitrite in inhaled form is no longer commercially available in cyanide antidote kits in the U.S. The FDA (as of September 2018) approves only Cyanokit (hydroxocobalamin injection), Nithiodote (sodium nitrite and sodium thiosulfate for intravenous infusion), sodium nitrite injection, and sodium thiosulfate injection for cyanide poisoning. Because amyl nitrite is absent from the FDA's approved list, OSHA no longer considers it acceptable. A 2018 expert consensus panel found hydroxocobalamin is the preferred antidote, with sodium nitrite and sodium thiosulfate also acceptable. All three available antidotes are administered by IV infusion and can only be given by healthcare professionals whose scope of practice includes IV drug administration.
For employers offering antidote therapy, OSHA says to provide an FDA-approved product, administer it soon after exposure to unconscious victims with known or strongly suspected cyanide poisoning, follow the product's 'Indications and Usage' labeling, and provide other interventions such as CPR, supplemental 100% oxygen, decontamination, and supportive care.
On the enforcement side, employers covered by the Medical Services and First Aid standard (29 CFR 1910.151(a)) whose workplaces have a foreseeable risk of cyanide exposure must consult with a physician or other licensed health care professional and ensure emergency medical services equipped with effective cyanide antidotes are readily available. That consultation should address storage, replenishment, pre-placement of emergency equipment, on-site staffing, training and licensing, EMS wait times, and worker susceptibility. OSHA states that the absence of such consultation is enforceable as a serious violation. Related standards may also apply, including exit routes and emergency planning (1910 Subpart E), dipping and coating operations (Subpart H), PPE (Subpart I), ventilation (1910.94), and hazard communication (1910.1200).