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NEC · NFPA · US
NEC Art. 506
Zone 20, 21, 22 Locations
Zone 20, 21, 22 Locations. Governs hazardous areas requirements for defense energetics facilities.
Changed in latest edition: Latest edition revised scope, definitions and testing criteria; review projects designed to the prior edition.
Applies to Features of Work (24)
- Propellant ExtrusionCritical
- Propellant CuringCritical
- Nitrocellulose HandlingCritical
- Hazardous VentilationHigh
- Emergency PowerMedium
- Propellant Mixing – Building 100High
- Propellant Casting – Building 100Critical
- Base Bleed Assembly – Building 100Critical
- Solvent Recovery – Building 100Critical
- Dust Collection – Building 100Low
- Electrical Substation – Building 100Medium
- Lightning Protection – Building 100Medium
- Propellant Extrusion – Building 200Low
- Propellant Curing – Building 200Critical
- Nitrocellulose Handling – Building 200Critical
- Hazardous Ventilation – Building 200High
- Emergency Power – Building 200Medium
- Propellant Mixing – Line ACritical
- Propellant Casting – Line AHigh
- Base Bleed Assembly – Line ACritical
- Solvent Recovery – Line ACritical
- Dust Collection – Line AHigh
- Electrical Substation – Line ALow
- Lightning Protection – Line AMedium
Required for Equipment (1)
- Explosion Isolation ValveExplosion Protection
Crosswalk
NEC Art. 506↔IEC 60079-10-2Dust zone classificationSimilar
NEC Art. 506↔EN 1993Anchor boltsPartial