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:
- Flammable or Combustible Material (in the correct quantity): presence of gases, vapours, flammable liquids, or combustible dusts.
- Oxidant: usually oxygen dissolved in the atmosphere;
- Ignition Source.
If any of these three factors is absent, an explosion cannot occur.
The ATEX directive
ATEX is the acronym for “ATmosphères EXplosives”.
It is a European directive that regulates equipment and protective systems intended for use in environments where there is a risk of explosion due to the presence of gases, vapours, flammable liquids, or combustible dusts.
The purpose of the ATEX Directive is to prevent explosions and fires in potentially hazardous environments by regulating the design, manufacture, commissioning, and use of equipment intended for use in such areas.
The ATEX Directive applies to all industries where flammable materials are present.
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.
What are the international standards for ATEX zones?
There are various international standards relating to explosive atmospheres. The main ones include: ATEX (Europe), IECEx (International), UKCA (UK), FM/UL (United States and Canada), Inmetro (Brazil), EAC (Russia), CCC (China)…
It is important to note that each country or region may have its own standards for explosive atmospheres, and companies must comply with these standards to ensure the safety of workers and equipment.
