This International Standard specifies test methods for the evaluation of fluids exposed to standard elastomeric materials that have been manufactured in accordance with the specified processes. It allows baseline comparisons of fluids with standard elastomers. This International Standard provides formulations, mixing and vulcanization procedures for five types of elastomeric compositions: a) acrylonitrile-butadiene rubber (NBR 1 and NBR 2); b) fluoroelastomers (FKM 2); c) ethylene propylene diene rubber (EPDM 1); d) hydrogenated NBR (HNBR 1). These procedures evaluate the effect of mineral-based, fire-resistant and biodegradable hydraulic fluids on such compositions by measurement, under controlled conditions, of physical properties of standard test pieces of the suitable test elastomer before and after immersion in the fluids. This International Standard does not provide formulations of elastomeric materials for actual service, however service elastomers may be tested using these compatibility procedures if required. NOTE The elastomeric materials used in these formulations are sensitive to fluid variations and have comparatively high swelling characteristics. Stable cure systems should be used to give adequate storage life.