The general description of hazardous areas and protection types in Canada are presented in Canadian Electric (CE Code) published by CSA. More specific requirements can be found e.g. from several IEEE and UL publications. Electrical equipment used in hazardous locations, classified according to North American rules, must be approved by an authorised body or the manufacturer. The equipment for Division 1, Zone 0 or Zone 1 areas must always be approved by an authorised body e.g. UL, CSA or FM.
Hazardous area equipment is allocated a Category depending on its degree ofprotection, indicating where the item can be used.
Equipment designed for very high level of safety. Requires two independent means of protection or safe operation with two separate faults. Used where explosive atmospheres are present continuously or for lengthy periods, typically Zone 0 and Zone 20.
Equipment designed for a high level of safety. Requires the design to be safe with frequently occurring disturbances or with one operating fault. Used where explosive atmospheres are likely to occur, typically Zone 1 and Zone 21.