Fire extinguisher in the early 60s and Purple-K being developed by the US Navy in the late 1960s. Manually applied dry agents such as graphite for class D (metal) fires had existed since WWII, but it wasn't until 1949 that Ansul introduced a pressurized extinguisher using an external CO2 cartridge to discharge the agent. Met-L-X (sodium chloride) was the first extinguisher developed in the US, with graphite, copper, and several other types being developed later. In the 1970s, Halon 1211 came over to the United States from Europe where it had been used since the late 40s or early 50s. Halon 1301
Fire extinguisher of fire safety legislation. Lack of maintenance can lead to an extinguisher not discharging when required, or rupturing when pressurized. Deaths have occurred, even in recent times, from corroded extinguishers exploding. In the United States, state and local fire codes, as well as those established by federal agencies such as the Occupational Safety and Health Administration, are generally consistent with standards established by the National Fire Protection Association (NFPA). They commonly require, for fire extinguishers in all buildings other than single-family dwellings, inspections every 30 days to ensure the unit is pressurized and unobstructed (done by an employee of the