【Safety Certification】Hazardous (Classified) Locations of USA in Article 505 of the NEC

The Classification System that found in Article 505:
- divides locations having gases and vapors into Class I, Zones (0, 1 & 2) and Gas Groups (IIA, IIB & IIC).
 
CLASS I
Locations where fire or explosion hazards may exist due to flammable gases, vapors, or liquids.
 
ZONES:
- Zone 0: a location where ignitible concentrations are present continuously or for long period of time under normal operating conditions.
- Zone 1: a location where ignitible concentrations are likely to exist under normal operating conditions.
- Zone 2: a location where ignitible concentrations are not likely to exist under normal operating conditions.
 
MATERIAL GROUPS:
- Group IIA – A typical material is propane.
- Group IIB – A typical material is ethylene.
- Group IIC – A typical material is hydrogen, Acetylene.
 
 
[Note]
- NEC - National Electrical Code of USA
- Article 505 covers the requirements for the zone classification system as an alternative to the division classification system covered in Article 500 for electrical and electronic equipment and wiring for all voltages in Class I, Zone 0, Zone 1 and Zone 2 hazardous (classified) locations.
 
GCS Safety Team