Ammonia Detection

In its anhydrous (dry) form, ammonia is a colourless gas at room temperature with a characteristic pungent, irritating odour. It is usually detectable by smell at less than 5 ppm. Ammonia is easily liquefied under pressure and dissolves in water to form ammonium hydroxide (NH₄OH). It burns in air to form nitric oxide (NO) and water.

 

Although it is a natural product of human, animal and plant metabolism, exposure to high concentrations can cause severe respiratory tract and eye irritation, even to the extent of causing temporary blindness. In industry, it is mainly used in the production fertilisers, in the production of chemicals such as nitric acid, acrylonitrile and aniline, and as a refrigerant gas.