Intrinsic Safety – Zones/Divisions (Canada/US)

Safety – Above All Else

When flammable substances are produced, processed, transported or stored, safety becomes the highest priority.  This is most relevant in oil and natural gas production, mining, petrochemical, and chemical industries.

To achieve the highest level of safety possible, province/state legislations have developed corresponding conditions through laws, regulations and standards.  These now have to be implemented by companies because the operator of a plant is solely responsible for safe operation in accordance with the directive 1999/92/EC.



Explosions – Causes

The 3 factors required to cause an explosion are:

  • Fuel (gas or dust)
  • Oxygen (O2)
  • Any ignition source (e.g. electric sparks, hot surface, short-circuit etc.)

The risk is based on the probability of a fuel and oxygen mix occurring over time.

ECOM‘s range of intrinsically safe devices and equipment ensure that potential ignition sources are removed or prevented.  By doing so, the risk of an explosion is eliminated.

The area of responsibility thereby extends to:

  • Stipulation of the explosive areas (zones)
  • Compilation of an explosion protection document
  • Realization of organizational and technical measures for explosion protection
  • Implementation of checks
  • use of products in Ex-areas that comply with the directive 2014/34/EU

IEC – Zone Division

Ex-Zones Definition

Areas subject to gas explosion:

  • Zone 0
    • An explosive atmosphere with a mixture of air and flammable substances in the form of gas, vapour or fog, either constantly or in the long term
  • Zone 1
    • It must be assumed that an explosive atmosphere with a mix of air and flammable substances in the form of gas, vapour or fog arise during normal operation
  • Zone 2
    • It must not be assumed that an explosive atmosphere with a mix of air and flammable substances in the form of gas, vapour or fog arise during normal operation and if so, then only rarely and for a short time

Areas with flammable dust:

  • Zone 20
    • An explosive atmosphere in the form of a cloud of flammable dust in the air, constantly, in the long term or frequently
  • Zone 21
    • It must be assumed that an explosive atmosphere in the form of a cloud of flammable dust in air sometimes occurs during normal operation
  • Zone 22
    • It must not be assumed that an explosive atmosphere in the form of a cloud of flammable dust in air occurs during normal operation, and if so, only for a short period of time

North American Division System:

The North American Division System considers only 2 possible likelihoods of explosive Fuel/Oxygen mixtures occuring:

  • Division 1
    • A mixture of flammable gas, dust or vapour occurs permanently or occasionally.  The same as Zone 1 and Zone 0
  • Division 2
    • The mixture occures only rarely and for a short amount of time.  The same as Zone 2