This AIR is intended to disseminate data relative to the compatibility of elastomers in order to aid in O-ring and sealant selection. A secondary purpose relates to the selection of solvents and cleaning agents for components and systems containing elastomeric sealants. This document contains data relative to the chemical nature of aerospace fluids and relates each to its effect upon elastomeric components. Since the compatibilities of elastomers are determined by the compounding as well as the nature of the base polymer, the elastomers considered are limited to finished compounds for which material or performance specifications could be referenced.