Chemical fire retardants commonly used are Optibor (boric acid, Neobor (borax pentahydrate) or borax decahydrate, ammonium sulfate, ammonium phosphates, aluminum sulfate, aluminum trihydrate and gypsum.
Cellulose, the basis of wood, cotton, and most other plant-derived raw materials, is in widespread industrial use. It is inherently flammable in many of its forms—paper being a typical example.
Firebrake ZB, a boron-based multi-functional fire retardant, has been used as flame retardant, smoke suppressant, and afterglow suppressant in both halogen-containing and halogen-free elastomers.
Firebrake ZB is a borate product used extensively as a partial or complete replacement for antimony oxide and other high-cost flame retardants in flexible polyvinyl chloride (PVC).