HAZARDOUS AREA EQUIPMENT

Zone Classification

Definition

The classification of a Zone is a complex problem with the main factors to consider:

  • The probability of the presence of Gas or Vapour or Dust
  • The quantity and duration of hazardous environment
  • The amount of ventilation
  • The nature of Gas being lighter or heavier than Air

The division of the plants or parts into Zones is generally undertaken by the supervisory authority in that industry with process engineers / chemists at the design and / or construction stage.

 

Zone 0 Continuously Hazardous ( Protection Technique Allowed)
Ex ia    Intrinsically Safe
Ex ma  Encapsulation
Zone 1 Frequently Hazardous (Protection Technique Allowed)
Ex ib   Intrinsic Safety
Ex d    Flameproof
Ex e    Increased Safety
Ex p    Pressurized or Purged
Ex s    Special Protection
Zone 2 Infrequently Hazardous (Protection Technique Allowed)
Ex n Non-sparking
 

Typical Example of Zone

Zone Group II Haz Area Pic

 

 

 

Serviceline Information