<Li> Potassium bicarbonate & Urea Complex (AKA Monnex), used on class B and C fires . More effective than all other powders due to its ability to decrepitate (where the powder breaks up into smaller particles) in the flame zone creating a larger surface area for free radical inhibition . Grey in color . </Li> <Li> Potassium chloride, or Super-K, dry chemical was developed in an effort to create a high efficiency, protein - foam compatible dry chemical . Developed in the 60s, prior to Purple - K, it was never as popular as other agents since, being a salt, it was quite corrosive . For B and C fires, white in color . </Li> <Li> Foam - compatible, which is a sodium bicarbonate (BC) based dry chemical, was developed for use with protein foams for fighting class B fires . Most dry chemicals contain metal stearates to waterproof them, but these will tend to destroy the foam blanket created by protein (animal) based foams . Foam compatible type uses silicone as a waterproofing agent, which does not harm foam . Effectiveness is identical to regular dry chemical, and it is light green in color (some ANSUL brand formulations are blue). This agent is generally no longer used since most modern dry chemicals are considered compatible with synthetic foams such as AFFF . </Li> <Li> MET - L - KYL / PYROKYL is a specialty variation of sodium bicarbonate for fighting pyrophoric (ignites on contact with air) liquid fires . In addition to sodium bicarbonate, it also contains silica gel particles . The sodium bicarbonate interrupts the chain reaction of the fuel and the silica soaks up any unburned fuel, preventing contact with air . It is effective on other class B fuels as well . Blue / red in color . </Li>

Who invented the first modern chemical based hand held fire extinguisher