Williams’ “PKW™” is a highly specialized siliconized Purple-K that is one of the most effective dry chemicals used to extinguish flammable and/or combustible pressurized liquid fires.  When used in conjunction with Hydro-Chem™ Technology it effectively controls and extinguishes pressurized or three dimensional “Class B” liquid fires.  Its distinctively deep purple color provides the fire fighter with the ability to stay ON-TARGET when projected to the fire within the foam and/or water stream.  The result, when combined with Hydro-Chem™ Technology is the ability to achieve a quicker and more efficient “knockdown,” and extinguishment.  Because it allows ON-TARGET delivery, it reduces waste, post-extinguishment cleanup efforts and costs.

Williams” “PKW™” is a potassium bicarbonate based dry chemical containing colorized additives.  The agent is free-flowing, water repellent and non abrasive and, when used as a fire extinguishing agent, will produce no toxic effects.  “PKW™” dry chemical is available in 50 pound plastic pails. 

Note: PKW™ contains 2.05% of Purple dye as compared to Ansul’s Standard Purple-K containing 0.0143% of the same dye.


Part No.

Williams: 13283; Ansul: 423650


Siliconized Purple K-Deep Purple Color


50 lb. Plastic Pail

Specific Application

For use with Hydro-ChemT Technology

General Application

Class "B" Liquid Fires