Classification of explosion protection zones
According
to Directive 2014/34/EU, a potentially explosive area is a space in
which the atmosphere could become explosive on account of the local
and/or operational conditions. These potentially explosive atmospheres
are divided into zones. Depending on the frequency and duration of the
occurrence of hazardous, explosive atmospheres. An explosive atmosphere
is defined as a mixture with air, under atmospheric conditions, of
flammable substances in the form of gases, vapours, mists or dust in
which, after ignition has occurred, combustion spreads to the entire
unburned mixture.
Hazard gas | vapoor | mist
Zone 0
A
place in which an explosive atmosphere consisting of a mixture with air
of dangerous substances in the form of gas, vapour or mist is present
continuously or for long periods or frequently.
Zone 1
A
place in which an explosive atmosphere consisting of a mixture with air
of dangerous substances in the form of gas, vapor or mist is likely to
occur in normal operation occasionally.
Zone 2
A
place in which an explosive atmosphere consisting of a mixture with air
of dangerous substances in the form of gas, vapor or mist is not likely
to occur in normal operation but, if it does occur, will persist for a
short period only.
Hazard powder | dust
Dust
clouds in the explosive region (above the minimum explosible
concentration) are categorized into 3 zones, based upon the grade of
release.
Zone 20
A place in which an explosive
atmosphere in the form of a cloud of combustible dust in air is present
continuously or for long periods or frequently.
Zone 21
A
place in which an explosive atmosphere in the form of a cloud of
combustible dust in air is likely to occur in normal operation
occasionally.
Zone 22
A place in which an
explosive atmosphere in the form of a cloud of combustible dust in air
is not likely to occur in normal operation but, if it does occur, will
persist for a short period only.
