This specification presents the performance classifications for biodegradable fire-resistant hydraulic fluids that are used in the industrial/mobile and mining industries. Covered here are seven material classes, as follows: HFA are fire resistant hydraulic fluids that may be further classified as HFAE, which are oil-in-water emulsions, and HFAS, which are chemical solutions not containing any emulsions; HFB, which are water-in-oil emulsions; HFC, which are aqueous monomer and polymer polyglycol solutions; HFD, which are phosphate ester or polyolester-based, water-insoluble fire-resistant fluids; HFDR, which are phosphate ester-based fluids; HFDU, which arewater-free fluids based on chemical compounds other than phosphate esters and chlorinated hydrocarbons; and HEPG, which are anhydrous "environmentally friendly" polyalkylene glycol-derived hydraulic fluids that may be water soluble or insoluble.

1.1 This specification covers performance classifications for biodegradable fire resistant hydraulic fluids that are used in the industrial/mobile and mining industries.

1.2 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and to determine the applicability of regulatory limitations prior to use.