Ammonia is DIFFICULT to ignite and exhibits a narrow range of flammability. It is flammable only at high concentrations and under EXTREMELY limited conditions. Because ammonia will not SUSTAIN a flame on its own, ignition of ammonia vapour requires an uninterrupted EXTERNAL flame source. Ammonia burning velocity, at a maximum of 8 cm/s, is substantially lower than other flammable refrigerants, and is not high enough to create an explosion. Properly designed ammonia refrigeration SYSTEMS that are well ventilated and free of open flames or ignition sources are safe against potential explosion.

Ammonia is difficult to ignite and exhibits a narrow range of flammability. It is flammable only at high concentrations and under extremely limited conditions. Because ammonia will not sustain a flame on its own, ignition of ammonia vapour requires an uninterrupted external flame source. Ammonia burning velocity, at a maximum of 8 cm/s, is substantially lower than other flammable refrigerants, and is not high enough to create an explosion. Properly designed ammonia refrigeration systems that are well ventilated and free of open flames or ignition sources are safe against potential explosion.