Specifies requirements and associated test methods for vulcanized rubber materials used in gas appliance and equipment in contact with 1st, 2nd, and 3rd family combustible gases. Also establishes a classification based on temperature range and hardness. Applies to materials from which are manufactured homogeneous or reinforced diaphragms. Does not apply to seals and diaphragms for devices in gas transmission systems nor in equipment used in 1st and 2nd family gas distribution systems.