The release of a possibly harmful gas within a crewed spacecraft. NASA requires that all materials used in habitable areas be tested for offgassing, flammability, and odour. This includes materials in experiments, stowed equipment, and parts of the spacecraft itself. Tests are carried out by the Toxicology Laboratory at the Johnson Space Center and at other NASA facilities. Examples range from battery chargers to urine kits. Gas is sometimes vented out into space; gas in the wet-trash stowage compartment is removed by connecting the container to a vent in the waste management system to send it overboard.