What does ATEX mean?

The acronym “ATEX” comes from “ATmosphere EXplosive” and refers to an atmosphere in which there is a mixture of flammable substances in the form of gases, vapours, mists or powdered combustibles, which can cause an explosion under certain conditions.

These conditions include the presence of an ignition that causes the flammable mixture to ignite. For companies that produce machinery for food production, ATEX certification is of fundamental importance to guarantee a safe working environment that complies with current regulations.

In order for a potentially explosive atmosphere to form, the flammable and/or combustible substance must be present in a certain concentration; if the concentration is too low (poor mixture) or too high (rich mixture) there is little tendency to form an explosion but a combustion reaction, or no reaction, can be produced.

The classification of ATEX AREAS

The classification of ATEX AREAS, i.e. places of risk, is a method for analysing and classifying the environment where explosive atmospheres can form due to the presence of gas or powder, in order to facilitate the correct choice, installation and operation of the equipment to be used safely in such an environment.

The ATEX AREAS classification also takes into consideration the ignition characteristics of the gas or powder, such as the energy and ignition temperature.

The classification of places has two main objectives:

  • the determination of the type of dangerous area
  • the extension of the area.

When determining where an emission of flammable gas or powder may occur, the probability and duration of the emission must be assessed, based on the degree of emission. For each level of emission, the factors necessary to establish the starting point for evaluating the presence or absence of an explosive atmosphere and to possibly determine the type and extent of the dangerous areas are evaluated.

The degrees of emission of the source

The ATEX EN 60079-10-1 regulation distinguishes three degrees of source emission:

Continuous emission level [3.4.2]

Continuous emission or one that is expected to occur frequently or for long periods. NOTE: Both the terms “frequently” and “long” are intended to describe an extremely high probability of a potential release. In this regard, these terms do not necessarily need to be quantified.

Emission grade first [3.4.3]

Emission which can be expected to occur periodically or occasionally during normal operation.

Emission level according to [3.4.4]

Emission which is not expected to occur in normal operation and, if it occurs, is likely to occur only infrequently and for short periods.

Types of zones and categories of equipment

The classification of ATEX zones and equipment categories represents a fundamental system for managing the risks linked to the formation of explosive atmospheres in industrial environments. 

The types of ATEX zones are distinguished based on the presence and probability of formation of explosive atmospheres:

  • Permanent danger: refers to situations in which the explosive mixture is constantly present, representing a high risk.
  • Frequent danger: indicates the high probability of formation of an explosive mixture during normal operation of the system.
  • Occasional danger: occurs only in cases of anomalous operation of the system, representing a more limited risk.

Presence of powder and gas

These risks are then associated with three types of areas based on the presence of gas and powder.


0: Permanent presence->1G

1: Occasional presence -> 2G or 1G

2: Rare presence -> 3G, 2G or 1G


20: Permanent presence-> 1G

21: Occasional presence-> 2G or 1G

22: Rare presence -> 3G, 2G or 1G

Equipment categories

These risks are then associated with three categories of equipment, which determine the level of protection:

  • Category 1: offers a very high level of protection, indicated when the explosive mixture is present constantly, for long periods or frequently.
  • Category 2: provides a high level of protection, indicated when the formation of an explosive mixture is likely.
  • Category 3: offers a normal level of protection, indicated when the probability of formation of an explosive mixture is low and this remains only for short periods.

Inox-fer for ATEX 

Considering the functionality of Inox-fer machinery, it is important to note that the mixers can be placed in potentially explosive areas and require adequate certifications. Our machinery is certified for the categories and environmental conditions envisaged: they offer a solid basis to guarantee the protection of operators and the continuity of activities in complex and at-risk industrial environments.

We can supply mixers for production in the following types of areas:

Zone1 2G

This zone indicates the presence of flammable gases in the form of explosive atmospheres occasionally. Category 2G means that equipment used in this area must ensure a high level of protection against explosions. This means that they must be designed and built with resistant materials suitable for potentially hazardous environments, such as stainless steel in this case.

Zone 21 2D, for Cat. 3G and 3D

In this area, there are combustible powder that can occasionally form explosive atmospheres. Category 2D requires equipment with a high level of protection against powder explosions. However, it is important to note that for categories 3G and 3D (indicating a rarer presence of flammable gases or powder), it is necessary to consider additional protection and safety measures, ensuring that the equipment is able to handle less frequent risk situations but more dangerous.

Zone 22

This area is dedicated exclusively to electrical components that can be used in environments where the formation of explosive atmospheres is rare or absent. Electrical equipment intended for this area must be designed and built with high safety standards, including appropriate insulation and materials resistant to specific environmental conditions. It is important to note that for this type of area we can only provide the machine with the ATEX certification for only electrical components and not entire machinery.

Do you want more information on Inox-fer mixers compliant with the ATEX Classification?