Ammonia is considered a high health hazard because it is corrosive to the skin, eyes, and lungs. Exposure to 300 parts per million (ppm) is immediately dangerous to life and health. Ammonia is also flammable at concentrations of approximately 15% to 28% by volume in air. When mixed with lubricating oils, its flammable concentration range is increased. It can explode if released in an enclosed space with a source of ignition present, or if a vessel containing anhydrous ammonia is exposed to fire. Fortunately, ammonia has a low odor threshold (20 ppm), so most people will seek relief at much lower concentrations.
Ammonia refrigeration is addressed in specific standards for the general industry.
How do I find out about employer responsibilities and workers' rights?
Workers have a right to a safe workplace. The law requires employers to provide their employees with safe and healthful workplaces. The OSHA law also prohibits employers from retaliating against employees for exercising their rights under the law (including the right to raise a health and safety concern or report an injury). For more information see www.whistleblowers.gov or Workers' rights under the OSH Act.
OSHA can help answer questions or concerns from employers and workers. To reach your regional or area OSHA office, go to the OSHA Offices by State webpage or call 1-800-321-OSHA (6742).
Small businesses may contact OSHA's free On-site Consultation services funded by OSHA to help determine whether there are hazards at their worksites. To contact free consultation services, go to OSHA's On-site Consultation webpage or call 1-800-321-OSHA (6742) and press number 4.
Workers may file a complaint to have OSHA inspect their workplace if they believe that their employer is not following OSHA standards or that there are serious hazards. Workers can file a complaint with OSHA by calling 1-800-321-OSHA (6742), online via eComplaint Form, or by printing the complaint form and mailing or faxing it to the local OSHA area office. Complaints that are signed by a worker are more likely to result in an inspection.
If you think your job is unsafe or if you have questions, contact OSHA at 1-800-321-OSHA (6742). Your contact will be kept confidential. We can help. For other valuable worker protection information, such as Workers' Rights, Employer Responsibilities, and other services OSHA offers, visit OSHA's Workers' page.
- Ammonia Refrigeration. OSHA eTool. Assists employers and employees in identifying and controlling the hazards associated with the operation and maintenance of ammonia refrigeration systems. Many of the requirements of the Process Safety Management Standard, 29 CFR 1910.119, are identified in this eTool as possible controls, and are useful as recommended practices, whether or not the ammonia refrigeration system is a covered process.