1.1 This specification covers requirements for fuel grade ethyl tertiary-butyl ether (ETBE) that may be used for blending with fuels for aviation spark-ignition engines where permissible. Other ETBE grades availa This specification covers requirements for fuel grade ethyl tertiary-butyl ether (ETBE) that may be used for blending with fuels for aviation spark-ignition engines where permissible. The requirements for ETBE that may be used for blending with fuels f