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.
Provides references that aid in beginning a PHA by recognizing process hazards.
- 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.