What is the ATEX Directive?
The ATEX Directive is a CE marking directive that describes which devices are allowed in an explosive atmosphere. The ATEX 2014/34/EU (the Directive 94/9/EG replaces) deals with "equipment and protection systems for intended use in hazardous areas". By complying with the directive, the product is therefore approved for sale (or marketing) within the European Union.
When does the ATEX directive have to be applied?
The conformity assessment according to the ATEX directive and finally CE marking is mandatory for all electrical and non-electrical devices intended for use in hazardous areas (see below). This serves to prove the conformity of the product with the ATEX directive and its suitability for placing on the EU market. CE marking according to ATEX serves to enable the free movement of products throughout the European Union. It should therefore be used if the product wishes to circulate throughout the European Economic Area.
The manufacturer is responsible for ensuring the conformity of his products with the directive and for the design and construction of his products in accordance with the essential safety and health requirements and for compliance with the procedures for assessing the conformity of the product.
Which products are explicitly excluded from the ATEX directive?
The directive does not apply to the following products:
- medical products (however, a CE marking for medical devices is required)
- products or equipment and protective systems containing explosive substances or unstable chemical substances
- products (devices) intended for domestic and non-commercial use
- personal protective equipment (however, a CE marking according to the PPE Regulation 2016/425 is necessary)
- seagoing vessels and movable offshore units, together with the equipment on board such vessels or units
- means of transport, that is, road, rail or water networks, as well as means of transport intended for the carriage of goods by air, public road or rail networks or by water. Vehicles intended for use in hazardous areas are also included.
What does the ATEX directive require for CE marking?
In order to be able to apply the CE marking to a product intended for use in explosion-proof areas, the product must be manufactured taking into account integrated explosion safety. For this purpose, the ATEX directive requires the implementation of certain measures depending on the classification of the danger zone.
What measures do manufacturers have to take to apply a CE mark?
The ATEX conformity assessment verifies and ensures that the product is designed and manufactured in such a way that measures have been taken to avoid dangerous situations, even in the event of operational disruptions. These measures taken by manufacturers (distributors) are as follows:
- prevent the formation of explosive atmospheres that can be generated or released by the product itself,
- to prevent the ignition of explosive atmospheres, taking into account the nature of each electrical and non-electrical source of ignition,
- should, however, an explosion occur, which could directly or indirectly endanger living beings or things, stop them immediately and/or limit the range of explosion flames and explosion pressures to a sufficient degree of safety.
In addition, care must be taken in the design that the actual or foreseeable environmental conditions are handled appropriately and any reasonably foreseeable misuse is taken into account. To ensure this, organizational measures under management are necessary.
What is the purpose of classifying hazardous areas in Ex zones?
In principle, the stricter the zone, the stricter the integrated explosion safety of the product and thus the measures to be implemented by the manufacturer.
In the conformity assessment according to ATEX, the risk assessment is carried out via the classification of the hazardous area in zones. The classification of the hazardous areas takes place in zones depending on the expected frequency and duration of the presence of an explosive atmosphere.
Which Ex zones must be taken into account in the conformity assessment according to ATEX?
Hazardous areas are classified into several zones. The risk of explosion can be justified either by gases, vapours, mists or dusts. Zones 0, 1 and 2 will be based on gases, vapours and fog. Where 0 denotes the zone with the greatest hazard and 2 with the lowest hazard, zones 20, 21 and 22 are based on dust.
Safe or non-hazardous areas are areas where an explosive gas or dust atmosphere is not expected to be present in such quantities that special precautions for the design, Installation and use of equipment are required.
How are the ATEX zones 0, 1 and 2 which are caused by gases, vapours and fog defined?
Zone 0 An area with a constant or frequent explosive gas atmosphere (over long periods of time). This zone is the most dangerous among the three zones of gases, vapors and mist. Examples of zone 0 are:
- paint spraying equipment or storage,
- gas storage or containment.
- possible hazardous situations could be surfaces of a flammable liquid directly into the atmosphere.
Zone 1 An area where "an explosive gas atmosphere consisting of a mixture of air or combustible substances occurs occasionally or regularly during normal operation. Examples of zone 1 or 2 are:
- chemical or petrochemical plants
Products that may occur in Zone 1 or 2 and may require CE marking are:
- ambulance
- reach trucks
- pallets
- Individual mechanical seals
Zone 2 An area in which, during normal operation, an explosive gas atmosphere consisting of a mixture of air or combustible substances normally does not occur or only briefly occurs. An example of a possible hazardous situation is the connection flange. Laugh from flammable liquid, which can form rarely or only for a short time.
How are the ATEX zones 20, 21 and 22 created by dust defined?
Zone 20 An area in which an explosive dust atmosphere in the form of a dust cloud is present in the air constantly, over long periods of time or frequently.
Some examples of Zone 20 include
- filter
- cyclones
- dust transport systems
- interiors of mixers
- mills
- dryers
- desiccators
Zone 21 An area where an explosive dust atmosphere in the form of a dust cloud can occasionally occur in the air during normal operation. For example
- Areas near filling and emptying points.
Zone 22 Area in which a dust-explosive atmosphere is expected to occur in the form of a cloud of dust contained in the air during normal operation, but which is only present for a short time.
for example
- areas near appliances that are opened occasionally
- dust transport systems
- interiors of mixers
- millers
- dryers
- grain mill
How do manufacturers check the conformity of the product with the ATEX directive?
As part of the CE conformity assessment procedure, the manufacturer analyses and confirms the conformity of the product with the measures prescribed by the ATEX Directive. Manufacturers usually carry out conformity assessment during the design and production phase of their products.
In addition, manufacturers are required to contact conformity assessment bodies or notified bodies to evaluate the products. These bodies are selected by the individual European member states.
Secondly, manufacturers must contact laboratories to carry out appropriate tests. Laboratories must be connected to a notified body in order to perform tests. Upon receipt of the report, the notified body shall issue a certificate proving the safety of the product. The certificate is a necessity for the free movement of the product throughout the EU market.
The certificate shall contain the following information: name and address of the manufacturer, description of the device and/or serial number, reference to relevant harmonised standards, where applicable reference to the specifications declaring conformity, Details of the signatory and the two end digits of the year of affixing the CE mark.
The manufacturer’s technical documentation required by 2014/34/EU shall include a description of the device or protection system, design and production drawings and plans, descriptions to explain the drawings and the operation of the product, include evidence of conformity of the product with harmonised standards, calculations and tests, test reports and the notified body’s certificate.
Finally, the CE marking is attached to either the device, the packaging or the instructions.
In the case of products of device groups I and II and device categories M 1 and 1, the EU type examination (Article 13 paragraph 1 a).
In the case of products of device groups I and II, device categories M 2 and 2 either: EU type-examination or conformity based on an individual test for internal combustion engines and electrical equipment. For other devices, internal production controls or conformity based on an individual test (Article 13 paragraph 1 b).
In the case of products of device category 3, either internal production control or conformity on the basis of an individual test (Article 13 paragraph 1 c).
Which harmonised standards are often taken into account in conformity assessment?
A harmonised standard has been given legal force by the European Commission and has begun the presumption of conformity with the essential safety and health requirements of the ATEX Directive. The list of harmonized standards is important for the manufacturers of ATEX devices that have used these European standards for CE marking. These harmonised standards are drawn up by the following organisations.
Some important harmonised standards are
Harmonized standards for compliance are then developed by European standardisation institutes. Both operators and device designers must be aware of the constant further development of international standards.
