Kripton
Kripton gas is a kind of rare gas. Krypton gas is often used in green light used in advertising light, and at the airport as an airplane landing light. If the electric current flows through the krypton lamps, the green light is very bright and able to penetrate the thick mist, hence often used inside the mine. The kripton lamp is also used as a camera scan light to allow images to be taken in the dark.