1、Recommended Practice for Classification of Locations for Electrical Installations at Petroleum Facilities Classified as Class I,Zone 0,Zone 1,and Zone 2API RECOMMENDED PRACTICE 505SECOND EDITION,AUGUST 2018Special NotesAPI publications necessarily address problems of a general nature.With respect to
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16、ntsPage1Scope.11.1Purpose.11.2Application.12Normative References .22.1General.22.2Industry Codes,Guides,and Standards.22.3Government Codes,Rules,and Regulations.43Terms,Definitions,and Acronyms.43.1Terms and Definitions .43.2Acronyms.124Basic Conditions for a Fire or Explosion.135Flammable and Combustible Liquids,Gases,and Vapors.135.1General.135.2Flammable and Combustible Liquids.135.3Flammable Highly Volatile Liquids.145.4Flammable Lighter-than-air Gases.145.5National Electrical Code Grouping