This specification specifies the material requirements, structural requirements, performance requirements, inspection rules, and inspection of explosion-proof electrical equipment such as explosion-proof operating columns, explosion-proof distribution boxes, explosion-proof circuit breakers, explosion-proof buttons, explosion-proof control boxes, explosion-proof switches, and junction boxes for marine engineering. Methods, markings, packaging and storage. This specification applies to the design, production, manufacturing and acceptance of explosion-proof electrical equipment installed in explosive environments that may generate or accumulate in places such as offshore engineering mobile platforms, fixed platforms and ships. This specification is applicable to low-voltage explosion-proof electrical equipment of AC systems with a rated frequency of 50Hz or 60Hz and a maximum conductor-to-conductor voltage not exceeding 1000V, or a DC system with a maximum instantaneous voltage not exceeding 1500V under rated working conditions.