A gas detector is a device that detects the presence of gases in an area, often as part of a safety system. This type of equipment is used to detect a gas leak or other emissions and can interface with a control system so a process can be automatically shut down. A gas detector can sound an alarm to operators in the area where the leak is occurring, giving them the opportunity to leave. This type of device is important because there are many gases that can be harmful to human life. It is widely used in manufacturing industries also used in rail tunnels for detection of poisonous gases like carbon monoxide. It is used in oil and gas industries to detect leakage of inflammable gases generating and alarm at very early stage of leakage and generating control signal for shut down of equipment, preventing any major fire accident.