Ammonia Health and Safety Guide - Health and Safety Guide 37

Ammonia is a colourless acrid-smelling gas at room temperature and normal atmospheric pressure. Most people can identify its odour at 35 mg/rn3 in air. It can be stored and transported as a liquid at a pressure of 10 atmospheres at 25 °C. Spilled liquid ammonia boils immediately, cooling its surroundings as it vaporizes. The gas dissolves readily in water; in solution it forms, and is in equilibrium with, ammonium ions (NH4 ). Ammonia solutions are alkaline and react with acids to form ammonium salts.