ATEX/IECEX guide

How an explosion occurs

An explosion is a rapid chemical reaction of a flammable substance with oxygen, resulting in the release of energy (in the form of heat and light).

An explosion can occur ONLY IF the following three factors are present simultaneously:

1. Flammable or Combustible Material (in the correct quantity): presence of gases, vapours, flammable liquids, or combustible dusts.
2. Oxidant: usually oxygen dissolved in the atmosphere;
3. Ignition Source.

If any of these three factors is absent, an explosion cannot occur.

What is ATEX classification?

The ATEX classification is a system for classifying hazardous areas based on the risk of explosion due to the presence of gases, vapours, flammable liquids, or combustible dusts.

This classification is used to determine the safety requirements for electrical and mechanical equipment used in these areas.

Areas are classified based on the likelihood and duration of the presence of explosive atmospheres. Zones are categorised as Zone 0, 1, 2 for gaseous atmospheres and Zone 20, 21, 22 for atmospheres with combustible dusts.

Equipment used in these areas must comply with the safety requirements of the ATEX Directive (94/9/EC) and be certified for safe use in explosion-risk areas.