Hazardous Areas are locations where the potential for fire or explosion exists because of gases, dust, or easily ignitable fibers or flyings in the atmosphere.
Zone 0: An area classified as Zone 0 will have ignitable concentrations of flammable gases, vapours or liquids either continuously present or present for long periods of time under normal operating conditions.
Zone 1: An area classified as Zone 1 is likely to have ignitable concentrations of flammable gases, vapours or liquids either present under normal operating conditions.
Zone 2: An area classified as Zone 2 is not likely to have ignitable concentrations of flammable gases, vapours or liquids either present under normal operating conditions.
Note : In North America ‘Divisions’ are used to categorise risk where Division 1 is equivalent to Zone 0 or 1 and Division 2 is equivalent to Zone 2.