A flammable gas detector is a device used to monitor or detect the presence of hazardous, combustible gases, such as natural gas, chlorine, methane, carbon monoxide, propane, and butane. These devices can be either portable hand-held devices or fixtures in a home, office, or facility. They are often used to detect leaks in gas lines, pipes, appliances, and storage tanks. Some are calibrated for a specific type of gas, while multi-gas detectors can sense the presence of various types of gases. A flammable gas detector may use one of many types of sensors, including catalytic bead sensors, explosimeters, or infrared devices.
Detectors measure the presence of gas in parts per million (ppm). Specific gases have different ranges of acceptable concentrations in parts per million. Flammable gases have an explosive limit, at which point the gas is liable to combust. The typical flammable gas detector will signal a warning if the concentration is above the safe range of parts per million, often with precise readings that determine the level of danger and record specific values.
In construction, inspectors and HVAC specialists often use a flammable gas detector to ensure all gas-related fittings and appliances meet with construction code and safety standards. Portable gas detectors are also worn by people working in environments that can accumulate high concentrations of toxic or flammable gases, such as mine shafts. Fixed detectors can be integrated into a safety system that, when dangerous gas levels are detected, will terminate any processes involving the gas or isolate contaminated areas. Many plants and manufacturing facilities employ such systems, some with remote monitoring and control capabilities.
Portable detectors are also useful for do-it-yourself home installations. When implementing gas-powered devices without the assistance of a professional, a portable detector can ensure that all pipes and fittings are properly sealed, and can identify problems caused by improper installation. Many toxic or flammable gases are mixed with a secondary substance with an identifiable smell. If, after installation, the smell of gas lingers, a portable detector can isolate the source.
In some places, regulations require installation of fixed flammable gas detectors in homes, offices, or any other facility with long-term human occupancy. The most common are natural gas detectors and carbon monoxide detectors. Central air and heating systems, hot water heaters, and gas stoves can all leak dangerous amounts of carbon monoxide or natural gas into the environment. Buildings without a flammable gas detector can also make periodic use of portable detectors to monitor gas concentrations or isolate the source of leaks.