The G-1B-R, G-1C-R, and G-2B-R Gasoline Fume Detectors are an effective means to monitor gasoline fumes in an engine compartments, leaking fuel tanks, or fumes from un-burnt hydrocarbons emitted from faulty exhaust systems. The systems use sensors, located in a place of interest, and a central display unit that notifies you of the state of the system.