OSHA Highlights Asphyxiation, Cryogenic Hazards of Flash-Freezing Operations

Flash-freezing processes that release liquid nitrogen and carbon dioxide present asphyxiation and cryogenic hazards for workers, OSHA stresses in a new hazard alert. The alert follows several recent agency investigations of fatal incidents involving nitrogen and carbon dioxide releases from flash freezers. OSHA explains that spiral and immersion freezers use nitrogen or carbon dioxide in solid, liquid, and vapor forms to rapidly freeze food products. But if equipment failure causes carbon dioxide or nitrogen to spill out into the work area, high concentrations of these substances can displace oxygen in the air, asphyxiating workers. OSHA’s hazard alert outlines precautions employers should take to help protect workers during flash-freezing operations.

Alarms to detect an oxygen-deficient atmosphere and emergency ventilation systems that can vent nitrogen and carbon dioxide releases are among the equipment employers can use to control these hazards. According to OSHA, employers must also train workers on emergency response and how to safely evacuate in case of a release. The agency alert also describes appropriate personal protective equipment to protect workers from respiratory and cryogenic hazards. For example, workers should have access to cryogenic gloves and respiratory protection such as a self-contained breathing apparatus. A combination full-facepiece pressure-demand supplied-air respirator with an auxiliary self-contained air supply would also be protective in this scenario, OSHA notes.

The hazard alert is available as a PDF from OSHA’s website.

Related: Read “Managing Asphyxiation Hazards from Cryogenic Gases” in the November 2024 Synergist.