For the purpose of this chapter, unless expressly provided
otherwise, the definitions below shall apply.
10.1.1
Hazardous area is an area
in which an explosive gas atmosphere is or may be expected to be present,
in quantities such as to require special precautions for the construction,
installation and use of electrical apparatusfootnote.
10.1.1.1
Zone 0 hazardous area is
an area in which an explosive gas atmosphere is present continuously
or is present for long periods.
10.1.1.2
Zone 1 hazardous area is
an area in which an explosive gas atmosphere is likely to occur in
normal operation.
10.1.1.3
Zone 2 hazardous area is
an area in which an explosive gas atmosphere is not likely to occur
in normal operation and, if it does occur, is likely to do so infrequently
and for a short period only.
10.1.2
Non-hazardous area is an area
in which an explosive gas atmosphere is not expected to be present
in quantities such as to require special precautions for the construction,
installation and use of electrical apparatus.