Zone Definitions

Definitions taken from IEC 60079-10-1 Area Classification.

1. Zone O

A place in which an explosive atmosphere consisting of a mixture with air of flammable substances in the form of gas, vapour or mist is present continuously or for long periods or frequently.

2. Zone 1

A piace in which an explosive atmosphere consisting of a mixture with air of flammable substances in the form of vapour or mist is likely to occur in normal operation occasionally.

3. Zone 2

A place in which an explosive atmosphere of a mixture with air of flammable substances in the form of gas, vapour or mist is not likely to occur in normal operation but, if it does occur, persists for a short period only.

Refer to Section 9.

For more detail, refer to EEMUA 186 - A Practitioner’s Handbook for potentially explosive atmospheres and relevant standards.