Zone 0:
An area where an explosive gas atmosphere resulting from the mixtureof flammable substances in the form of gas, vapor, or mist with air is present continuously, for very long periods, or frequently. This area is the most hazardous category in the classification of hazardous areas. (Locations such as the interiors of containers holding explosive substances and the internal parts of equipment handling explosives fall into this category.)
Zone 1:
An area where an explosive gas atmosphere resulting from the mixtureof flammable substances in the form of gas, vapor, or mistwith air is occasionally present during normal operation. (This group includes areas such as the immediate vicinity of Zone 0, flammable substance pump stations, and areas near valves and dampers.)
Zone 2:
An area where the presence of an explosive gas atmosphere resulting from the mixtureof flammable substances in the form of gas, vapor, or mistwith air is unlikely to occur during normal operation, and if it does occur, it lasts only for a very short time.(Only facilities or parts of facilities with welded pipe connections, as well as natural gas and oil pipelines, fall into this category.)
Zone 20:
An areawhereexplosivedustis present continuously, for a very long period of time, or frequently.
Zone 21:
An area where explosivedustis occasionally present during normaloperation.
Zone 22:
An areawherethe presenceofexplosivedustis unlikely during normal operation, and if present, it lasts only for a very short time.
Division 1 covers areas where explosive atmospheres are present or are highly likely to form under normal operating conditions, and where such conditions persist for extended periods.
Normal çalışma koşullarında patlayıcı ortam oluşma ihtimali az olan yerler. Ancak anormal hallerde (tamir bakım, arıza, kaza gibi) patlayıcı ortam oluşan ve oluşma ihtimali olan ve kısa süren yerler DIVISION 2 kapsamındadır.
Flammable gases and vapors.
Explosive dusts, such as coal dust, flour, and sugar dust.
Airborne dust. Particles that are generally larger than ordinary dust. Examples include cotton dust, sawdust, and textile lint. These materials are not explosive but are flammable and pose a fire hazard.
