At what concentration does ammonia become flammable?

Ammonia becomes flammable at concentrations between 150,000 and 270,000 parts per million (ppm). This concentration range reflects the upper flammability limits of ammonia in the air, which is critical information for refrigeration engineers working with ammonia systems. Understanding these limits helps ensure safety in environments where ammonia is present, particularly in the context of leak prevention, emergency preparedness, and proper safety protocols.

In contrast, the other provided options fall outside this flammable concentration range. The range of 4,000 to 7,000 ppm and 5,000 ppm are below the lower threshold for flammability, while 800 ppm is significantly low and also does not approach the flammability limit. Recognizing these distinctions is essential for professionals in the field to maintain safe working conditions and respond correctly to potential hazards.