Introduction to Health and Safety at Work

17.12.10 References
The Dangerous Substances and Explosive Atmosphere 
Regulations 2002 SI 2002 No 2776
ISBN 0-11-042957-5
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.
Zone 1 
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 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, vapour or mist 
is not likely to occur in normal operation but, if 
it does, will persist for a short period only.
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.
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.
Table 17.4 Classifi cation Zones
Introduction to Health and Safety at Work
344

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Fire and Explosions How safe is your workshop. A short 
guide to DSEAR, HSE INDG370 (rev1), 2002 HSE Books, 
ISBN 0-7176-2956 2
Safe use and handling of fl ammable liquids HSG 140 
HSE Books
ISBN 0-7176-0967-7
Safe handling of combustible dusts; precautions against 
explosion HSG 103 HSE Books 1994
ISBN 0 7176 0725 9
Storage of dangerous substances, L135
Dangerous Substances and Explosive Atmospheres 
Regulations 2002.
Approved Code of Practice and guidance First published 
2003 HSE Books,
ISBN 0 7176 2200 2
Control and mitigation measures, L136
Dangerous Substances and Explosive Atmospheres 
Regulations 2002
Approved Code of Practice and guidance, First pub-
lished 2003 HSE Books,
ISBN 0 7176 2201 0
Safe maintenance, repair and cleaning procedures, L137
Dangerous Substances and Explosive Atmospheres 
Regulations 2002
Approved Code of Practice and guidance, First pub-
lished 2003 HSE Books,
ISBN 0 7176 2202 9
Dangerous substances and explosive atmospheres, L138
Dangerous Substances and Explosive Atmospheres 
Regulations 2002
Approved Code of Practice, First published 2003 HSE 
Books
ISBN 0 7176 2203 7