An ammonia gas detector is generally used to determine the presence of ammonia in areas that can contain high ammonia levels in the air. Areas where an ammonia gas detectors are generally useful include airtight storage rooms, engine rooms and chemical plants. Ammonia is a type of gas that is colorless and has a stinging odor. The gas reacts when mixed with water and can potentially cause damage to the eyes, the skin, and the respiratory system. It is lighter than air and is generally flammable.
A threshold limit for storage of ammonia has been set to approximately 10,000 pounds (about 4,535 kilograms) for the anhydrous type and 20,000 pounds (about 9,071 kilograms) for the hydroxide type. Once this threshold is exceeded, the facility is required to comply with several regulations, like putting up ammonia gas detectors in the area. These companies also need to follow control procedures as mandated by law including providing insurance for their personnel.
There are various types of ammonia gas detectors used in various industries. One of the most common ammonia gas detectors being used in storage rooms is the ultraviolet gas leak detector. With the use of ultraviolet (UV) light being passed on the air sample, it can detect the presence of ammonia. Another widely used ammonia gas detector is the electrochemical ammonia gas detector. This one utilizes an electrolyte fluid with an absorbent membrane to detect ammonia in the air. Most ammonia gas detectors come with an alarm system consisting of a bell, phone dialer, and valves.
Other types include the semi-conductor and the solid state detectors. A semi-conductor ammonia gas detector is frequently used to detect levels of ammonia as low as 50 parts per million (ppm) either outdoors or in engine rooms. The solid state sensor is another detector often preferred by many facilities for its long life, cheap cost, and excellent reliability. It may also be used in detecting other gases such as carbon monoxide, propane, and methane.
Ammonia gas detector monitors are usually placed in specific areas such as near the storage room, loading rack, injection area, and other places where equipment for handling of ammonia fluid are usually placed. These areas are often considered at high risk for ammonia leakage. Because ammonia gas is lighter than air, most ammonia gas detectors are positioned near the breathing zone. The spacing of the sensors is determined by specific hazards and risks posed to personnel.