Encyclopedia
First Class
Class I — zones in which flammable gases or vapors of easily ignitable liquids are released during normal equipment operation, forming explosive mixtures with air1;
Federal Law No. 123-FZ dated 22.07.2008 "Technical Regulation on Fire Safety Requirements", as amended on 2019-07-01, Article 19, subpara. 2 // RSFSR Gazette. 2008. No. 30. Item 3579. ↩