NFPA 497:2021
Superseded
A superseded Standard is one, which is fully replaced by another Standard, which is a new edition of the same Standard.
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Recommended Practice for the Classification of Flammable Liquids, Gases, or Vapors and of Hazardous (Classified) Locations for Electrical Installations in Chemical Process Areas
Hardcopy
31-05-2023
English
16-08-2021
Important note : Users cannot be edited or removed once added to your Multi user PDF.Chapter 1 Administration 1.1 Scope. 1.2 Purpose. 1.3 Relationship to NFPA Codes and Standards. Chapter 2 Referenced Publications 2.1 General. 2.2 NFPA Publications. 2.3 Other Publications. 2.4 References for Extracts in Recommendations Sections. Chapter 3 Definitions 3.1 General. 3.2 NFPA Official Definitions. 3.3 General Definitions. Chapter 4 Classification of Combustible Materials 4.1 National Electrical Code Criteria. 4.2 Behavior of ClassI (Combustible Material) Gases, Vapors, and Liquids. 4.3 Conditions Necessary for Ignition. 4.4 Classification of ClassI Combustible Materials. Chapter 5 Classification of ClassI (Combustible Material) Areas 5.1 National Electrical Code (NEC). 5.2 General. 5.3 Class, Division, Classified Locations. 5.4 Zone Classified Locations. 5.5 Unclassified Locations. 5.6 Extent of Classified Locations. 5.7 Discussion of Diagrams and Recommendations. 5.8 Basis for Recommendations. 5.9 Procedure for Classifying Locations. 5.10 Classification Diagrams for ClassI, Divisions. 5.11 Classification Diagrams for Zones. Annex A Explanatory Material Annex B Example of a Method for Determining NEC Group Classification for Mixtures Annex C Informational References
This recommended practice applies to those locations where flammable gases or vapors, flammable liquids, or combustible liquids are processed or handled; and where their release into the atmosphere could result in their ignition by electrical systems or equipment.
| DocumentType |
Standard
|
| Pages |
79
|
| ProductNote |
This standard is also refers to API RP 505:2002(R2013),ASTM D323:2008(R2015),ISA-RP12.12.03:2011.
|
| PublisherName |
National Fire Protection Association
|
| Status |
Superseded
|
| SupersededBy | |
| Supersedes |
| NFPA 820:2024 | Standard for Fire Protection in Wastewater Treatment and Collection Facilities |
| NFPA 318:2025 | Standard for the Protection of Semiconductor Fabrication Facilities |
| NFPA 318:2022 | Standard for the Protection of Semiconductor Fabrication Facilities |
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