At ordinary temperatures, it is a colorless gas, but under pressure it changes into a liquid. Agricultural ammonia is transported, stored and handled in pressurized tanks. Anhydrous ammonia is a strong alkali that can cause painful skin burns. Because of its low boiling point, anhydrous ammonia can burn by freezing as well as by caustic action. Even mild exposure can cause irritation to tissues of the eyes, nose and lungs.
Prolonged breathing can cause suffocation.
However, the water-absorbing nature of ammonia causes the greatest injury, especially to the eyes. Permanent damage can result. Handling It Safely Anhydrous ammonia can be used as safely as any other gas or liquid that is handled under pressure. But you must be alert to prevent accidents. One good thing about ammonia is that its sharp, irritating odor is an excellent warning.