Section 2 Definitions

201. Definitions of Terms

The following definitions of terms are to be understood (in the absence of other specifications) where they appear in this Chapter.

1. Hazardous Areas

Hazardous areas are all those areas where a flammable atmosphere may be expected to exist continuously or intermittently. Hazardous areas are subdivided into Zones 0, 1, 2, defined as follows:

(1) Zone 0 : A zone in which ignitable concentrations of flammable gases or vapors are con- tinuously present or present for long periods.

(2)

Zone 1 : A zone in which ignitable concentrations of flammable gases or vapors are likely to

occur in normal operating conditions.

(3) Zone 2 : A zone in which

likely to occur in for a short time.

ignitable concentrations of flammable gases or vapors are not normal operating conditions, and if it occurs, it will exist only

52 Guidance for Offshore Support Vessels 2015