Resources
Zone
The international method of specifying the probability that a location is made hazardous by the presence, or potential presence, of flammable concentrations of gases and vapors. NOTE: Zone classification has not yet been defined for dust.
Zone 0: Classification of a location in which an explosive concentration of a flammable gas or vapor mixture is continuously present or is present for long periods.
Zone 1: Classification of a location in which an explosive concentration of a flammable or explosive gas or vapor mixture is likely to occur in normal operation.
Zone 2: Classification of a location in which an explosive concentration of a flammable or explosive gas or vapor mixture is unlikely to occur in normal operation and, if it does occur, will exist only for a short time