ATEX: A short introduction

  • ATEX (from French ATmosphères EXplosibles) covers two EU directives: Workplace Directive 1999/92/EC (ATEX 137) for employers/plant operators and Product Directive 2014/34/EU (ATEX 114) for manufacturers/equipment.
  • Manufacturers must ensure equipment and protective systems comply with the Product Directive and carry the required conformity documentation/marking.
  • Employers must comply with national laws transposing the Workplace Directive: assess explosion risks, classify hazardous areas, and prepare an Explosion Protection Document.
  • Zone calculations and classification must follow the technical standards (e.g., EN/IEC 60079-10-1 for gases/vapours; EN/IEC 60079-10-2 for combustible dusts).
  • Zones and equipment categories determine required protection; companies must apply appropriate technical/organisational measures, provide proportionate training, and keep inspection/maintenance documented.

Fundamentals of the ATEX directives

The ATEX directives on explosion protection are based on two main directives - the ATEX Workplace Directive 1999/92/EC ("ATEX 137") and the ATEX Product Directive 2014/34/EU ("ATEX 114"). These two directives are addressed to manufacturers, operators, and users of equipment or protective systems used in potentially explosive atmospheres. The detailed technical evaluations and zone calculations must be carried out in accordance with relevant technical standards (e.g., EN/IEC 60079-10-1 for gases and EN/IEC 60079-10-2 for combustible dusts).

UEBEX meets these requirements with ATEX-certified product families such as LUMEX SW, LUMEX OR and LUMEX HB, which are designed for different zones and applications.

ATEX Product Directive

The ATEX Product Directive stipulates that equipment, components, and protective systems intended for use in potentially explosive atmospheres may only be sold or placed on the market if they comply with the specific requirements of this directive. This is intended to ensure that they do not cause explosions under normal operating conditions.

Definition: Equipment and components

"Equipment" includes machines, apparatus, fixed or mobile equipment, control and instrumentation parts as well as systems for warning and prevention. "Components" are parts that are necessary for the safe operation of equipment and protective systems but do not perform an independent function.

ATEX Workplace Directive

The European ATEX Workplace Directive is primarily aimed at employers and plant operators. It defines minimum requirements for improving the health protection and safety of employees who may be endangered by working in potentially explosive environments.

Product Directive 2014/34/EU Workplace Directive 1999/92/EC
Requirements for manufacturers of products Requirements for employers and plant operators
ATEX category classification ATEX zone classification
Risks and ignition sources of equipment are analyzed Hazard areas in operational areas are analyzed
Declaration of conformity Explosion protection document
ATEX Guide

There is an ATEX Guide for ATEX Directive 2014/34/EU that serves as guidance for all parties dealing with equipment and protective systems in potentially explosive atmospheres. However, it is not a legally binding document.

Important note

The ATEX Directives set the EU framework; specific sanctions and enforcement mechanisms are established in each Member State’s implementing legislation.

Importance of the ATEX directives

  • Protecting safety in potentially explosive environments
  • Harmonising product safety for equipment used in explosive atmospheres
  • Facilitating the free movement of compliant goods within the EU
  • Protecting workers by assigning employer obligations and risk-management duties

What are potentially explosive areas?

Potentially explosive areas (Ex areas) are locations where a hazardous explosive atmosphere may occur. An explosive atmosphere is defined as a mixture of air and flammable gases, vapors, mists, or combustible dust. It is considered hazardous only when its concentration and duration are sufficient to create a real risk of ignition and explosion.

The ATEX framework requires hazardous areas to be classified according to the explosion risk. Areas are assigned to Ex protection zones: gas zones 0, 1, 2 and dust zones 20, 21, 22. (Note: equipment categories are a separate classification for devices.)

ATEX zones

The ATEX directive provides that these areas are classified into different categories depending on the explosion hazard. These categories are divided into three ATEX zones or Ex protection zones. Two main types of zones are distinguished: gas Ex zones (0, 1, 2) and dust Ex zones (20, 21, 22).

Explosive atmosphere Flammable gases Flammable dusts
(typically) Present continuously or for long periods (over 1000 hrs per year) Zone 0 Zone 20
(typically) Present occasionally (over 10 and under 1000 hrs per year) Zone 1 Zone 21
(typically) Present only briefly (under 10 hrs per year) Zone 2 Zone 22

Equipment categories

Equipment in Category 1 provides the highest level of safety and can be used in all zones, including the most explosion-prone zones 0 and 20.

Equipment category Use in
1 Zones 0, 1, 2, 20, 21 or 22
2 Zones 1, 2, 21 or 22
3 Zones 2 or 22
Important for practice

Classification of Ex areas requires a thorough on-site assessment by qualified personnel to identify hazards, determine zone boundaries and select appropriate protective measures. Assessments should consider the frequency, duration and likelihood of explosive atmospheres and the presence of ignition sources.

Marking of ATEX equipment

According to the ATEX directive, every device, protective system, and installation used in potentially explosive areas must contain the following minimum information:

Practical examples from our portfolio can be found with LUMEX OR, LUMEX OC and LUMEX EM, which cover different marking variants for gas and dust zones.

  • Name, registered trade name or registered trademark and address of the manufacturer
  • CE marking and number of the involved notified body
  • Designation of the series and type
  • If applicable, the batch or serial number
  • The year of construction
  • The explosion protection marking, followed by the marking that identifies the equipment group and category

Equipment groups

The ATEX directive divides products into two equipment groups depending on the area of use:

Equipment group For use in
I Mines (above and below ground)
II All other potentially explosive areas (non-mining)

Equipment categories and safety levels

Equipment category Avoidance of effective ignition sources Level of safety Usable in zones Presence of explosive atmospheres
3 In normal operation normal 2, 22 rare and short-term
2 Also during expected malfunctions high 1, 2, 21, 22 occasional
1 Also during rare malfunctions very high 0, 1, 2, 20, 21, 22 long-term, continuous or frequent

Explosion groups

According to their ignition capability and explosion propagation, gases are classified into explosion groups. The hazard of the gases increases from group IIA to IIC.

Explosion group (gas) Example gas
IIA Propane
IIB Ethylene
IIC Hydrogen

Temperature classes

The temperature classes T1–T6 and their maximum surface temperatures are defined in the IEC/EN standards, primarily IEC 60079-0; the ATEX framework refers to these standards for temperature class requirements.

Temperature class Permissible max. surface temperature Ignition temperature range of gas-air mixtures
T1 450 °C >450 °C
T2 300 °C 300-450 °C
T3 200 °C 200-300 °C
T4 135 °C 135-200 °C
T5 100 °C 100-135 °C
T6 85 °C 85-100 °C

Types of protection

The type of protection classifies various technical measures that ensure no ignition sources occur on equipment or during its operation:

  • Flameproof enclosure (Ex d): Flameproof enclosure that contains and prevents explosion propagation (Gas, EN/IEC 60079-1)
  • Increased safety (Ex e): Increased safety to avoid arcs, sparks and hot surfaces in normal operation (Gas, EN/IEC 60079-7)
  • Intrinsic safety (Ex i): Intrinsic safety: energy-limited circuits that cannot ignite an explosive atmosphere (Gas, EN/IEC 60079-11)
  • Pressurization (Ex p): Pressurization (positive pressure) to keep explosive atmosphere out of the enclosure (Gas, EN/IEC 60079-2)
  • Oil immersion (Ex o): Oil immersion of live parts to prevent sparks/hot surfaces from contacting atmosphere (Gas, EN/IEC 60079-6)
  • Encapsulation (Ex m): Encapsulation of components in a compound to isolate ignition sources (Gas, EN/IEC 60079-18)
  • Powder filling (Ex q): Powder filling of enclosure with non-combustible powder to prevent ignition (Gas, EN/IEC 60079-5)
  • Type of protection for Zone 2 (Ex n): Restricted-sparking / non-sparking measures intended for equipment for Zone 2 (Gas, EN/IEC 60079-15)
  • Measures for dust atmospheres (Ex t): Measures for dust atmospheres (control of surface temperature, enclosure protection) (Dust, EN/IEC 60079-31)
  • Special type of protection (Ex s): Special/non-standard protection concepts requiring specific assessment (Gas or Dust)

ATEX certification: necessity and process

ATEX (Directive 2014/34/EU) defines requirements for equipment and protective systems intended for use in potentially explosive atmospheres. Any product that can act as an ignition source in such atmospheres must be assessed and declared conformant before being placed on the EU market.

Products commonly in scope

  • Electrical equipment: switches, luminaires, motors, sensors, control gear
  • Mechanical equipment: pumps, valves, tools, enclosures, containers
  • Mobile devices: handheld computers, tablets used in hazardous areas
  • Measurement and control devices: sensors, controllers, regulators

Key requirements and conformity steps

  • Risk assessment: identification of potential ignition mechanisms and definition of the protection concept
  • Classification: assignation of the product to an equipment category (1, 2, 3) and the intended zone (gas: 0/1/2; dust: 20/21/22)
  • Standards and design: application of the relevant harmonised standards (e.g., EN/IEC 60079 series) or equivalent technical solutions
  • Conformity assessment procedure: following of the appropriate route (internal production control or involvement of a notified body)
  • Technical documentation: preparation of design drawings, risk assessment, test reports, bill of materials and user/maintenance instructions
  • Marking and declaration: after successful assessment, issuing of the EU Declaration of Conformity and application of the CE/Ex marking
Notified Body

For equipment categories that require external assessment, a notified/accredited body performs type-examination, testing and/or quality system assessment and issues the certificate. The notified body also supports the manufacturer with testing and formalities when needed.

ATEX conformity

ATEX conformity is confirmed at the end of the applicable conformity assessment procedure. Where required, a notified body issues a type-examination certificate; the manufacturer issues the EU Declaration of Conformity and applies the CE marking and, where applicable, the Ex marking with the relevant protection codes and notified-body number. Compliance with ATEX allows placing the product on the EU market.

Practical implementation of ATEX in the company

Companies operating in potentially explosive atmospheres must comply with the requirements of the ATEX directives, as well as all applicable national and local regulations, ensuring proper risk assessment, zone classification, and the use of compliant equipment and procedures.

Training and awareness measures

  • Personnel involvement: Active participation of employees in implementing explosion-protection measures
  • Targeted training: Regular training sessions on ATEX risks, zone classification, Ex markings, and safe operating procedures
  • Clear communication: Clear and accessible communication of safety instructions and operational limitations
  • Periodic verification: Regular inspections, audits, and competency checks to ensure ongoing ATEX compliance

Checklist - selection of explosion-protected equipment

When selecting equipment for use in potentially explosive atmospheres, safety specialists must verify that it meets all ATEX requirements and is suitable for the specific classified area.

  • Explosion-protection marking: verify that the equipment carries the correct and complete Ex marking
  • Equipment group: ensure the equipment belongs to the appropriate group, typically Group II for gas and dust applications
  • Equipment category: confirm that the category (1, 2, or 3) is suitable for the designated ATEX zone
  • Maximum surface temperature: check that the temperature class or maximum surface temperature is compatible with the substances present
  • Special conditions: review any “X” marking or manufacturer-specified special conditions of use
Important note

These measures enhance personnel awareness of ATEX obligations and help ensure that operational practices remain compliant in potentially explosive areas.

Safety and compliance in potentially explosive areas

The ATEX directives provide the framework for ensuring the conformity and safe use of equipment and protective systems in hazardous areas. Regular staff training and correct equipment marking are essential, together with compliance with any additional national or local regulations applicable to potentially explosive atmospheres.

UEBEX ATEX-certified lighting solutions

At UEBEX we offer professional LED lighting solutions that are specifically developed and ATEX-certified for use in potentially explosive areas. Our products meet the highest safety standards and are suitable for various ATEX zones.

Our ATEX product families

Product family Description
LUMEX N7 Dual Certification Compact Luminaire (Group I & II)
LUMEX SW Ultra-Heavy-Duty Mining Luminaire for Blasting Operations
LUMEX OR Heavy Duty Mining Luminaire
LUMEX OC Heavy-Duty Mining Luminaire for Inline Installation
LUMEX HB High Bay and Floodlight Solutions for Halls and Outdoor Areas
LUMEX ML Versatile Indoor Luminaire
LUMEX EM Heavy-duty IP66 luminaire suitable for aggressive industrial atmospheres
LUMEX LG Elegant Aluminium Luminaire
LUMEX LB Heavy Duty Lantern for Petrochemical Industry
LUMEX LS Emergency Sign Luminaire

Marking example: LUMEX ML (version for Zones 2/21)

Example of a breakdown of a LUMEX luminaire:

ATEX marking according to EN/IEC 60079-0.

II 3G Ex ec IIC T5 Gc

Permitted hazardous zones gas: 2 / dust: 21-22

Explosion group gas: IIC, IIB, IIA / dust: IIIC, IIIB, IIIA

Breakdown of the ATEX codes

  • II Equipment Group II (Ex-classified environments not mining-related).
  • 3G Category 3 for gas atmospheres (Suitable for Zone 2).
  • Ex Explosion-protected equipment marking (compliance with EN/IEC 60079 standards).
  • ec Type of protection "Increased safety" (Defined in EN/IEC 60079-7, intended for Zone 2 applications).
  • IIC Gas group with the highest requirements (Includes highly explosive gases such as hydrogen and acetylene).
  • T5 Temperature class. T5 stands for max surface temperature 100°C.
  • Gc Equipment Protection Level (EPL) for gas Level Gc, suitable for Zone 2.
UEBEX advantage

All our ATEX-certified lighting solutions are delivered with complete documentation and a declaration of conformity. Our experts will be happy to advise you on selecting the right luminaires for your specific ATEX requirements.

Summary

Correct application of the ATEX directives is essential for:

  • Ensuring the safety of employees in potentially explosive atmospheres
  • Maintaining legal compliance and avoiding sanctions
  • Protecting facilities and equipment
  • Guaranteeing reliable operation
  • Enabling pan-European market access for products

Correct application of the ATEX directives is essential, but it is not sufficient on its own; it must always be complemented by the applicable national workplace safety regulations.

Frequently asked questions about ATEX (FAQ)

Below you will find frequently asked questions about the ATEX directives and the marking of devices in potentially explosive environments.

What is the ATEX directive?
The term “ATEX directive” actually refers to two separate EU directives that deal with explosion protection in different ways. Together, they define the rules for equipment and workplaces in potentially explosive atmospheres.
  • ATEX Product Directive (2014/34/EU): This directive applies to manufacturers. It defines the essential health and safety requirements for equipment and protective systems intended for use in potentially explosive atmospheres. It covers the design, testing, certification, and marking of ATEX-compliant products.
  • ATEX Workplace Directive (1999/92/EC): This directive applies to employers and plant operators. It sets the minimum safety requirements for workplaces where explosive atmospheres may occur. It includes risk assessment, classification of hazardous zones, and organizational/technical measures to protect workers.
Do the ATEX directives contain technical instructions?
No. The ATEX directives do not provide technical instructions or detailed engineering methods. Both ATEX directives (2014/34/EU and 1999/92/EC) define legal requirements, not technical guidelines. What the directives provide: General safety objectives, essential health and safety requirements, obligations for manufacturers and employers, and rules for equipment categories. What they do not provide: No engineering methods, no practical procedures, and no technical design rules. Technical guidance is provided by harmonized standards (e.g., the EN/IEC 60079 series), which explain how to meet the requirements set by the directives.
What is meant by ATEX certification?
ATEX certification confirms that a device or machine complies with the requirements of the ATEX Product Directive (2014/34/EU) and is safe to use in potentially explosive atmospheres. The term ATEX comes from the French “ATmosphères EXplosibles.” A product with ATEX certification has been assessed according to the relevant conformity procedures, tested where required, and marked with the appropriate ATEX category, equipment group, and protection level. This ensures that the device is suitable for operation in environments where flammable gases, vapors, or dusts may create an explosion risk.
When must the ATEX directive be applied?
The ATEX Product Directive (2014/34/EU) applies to all electrical and non-electrical equipment intended for use in potentially explosive atmospheres. Any product placed on the EU market for operation in such environments must undergo the appropriate conformity assessment procedure and carry the CE and ATEX marking. Compliance with the directive is the manufacturer’s responsibility.
Does ATEX certification always require a Notified Body?
No. ATEX certification does not always require a Notified Body. Under the ATEX Product Directive (2014/34/EU), some lower-risk equipment categories can be certified directly by the manufacturer through self-declaration, without NB involvement. However, involving a Notified Body is considered good practice, even when not strictly required, because it provides independent verification of compliance and increases confidence in the product’s safety. All UEBEX products are certified by an independent Notified Body, including those for which the directive would allow self-certification.
Which products are exempt from the ATEX directive?
According to the scope and exclusions defined in Directive 2014/34/EU, the directive does not apply to:
  • Personal protective equipment covered by Regulation (EU) 2016/425
  • Products intended for use in domestic or non-commercial environments, where explosive atmospheres are not expected
  • Medical devices used in medical environments
  • Equipment, protective systems, and components containing explosive substances or unstable chemical substances (e.g., pyrotechnics)
Which industries and sectors are the ATEX directives relevant for?
The ATEX directives apply to any industry where explosive atmospheres may occur due to flammable gases, vapors, mists, or combustible dusts. This includes:
  • Mining (especially coal mines with firedamp or coal dust)
  • Chemical and petrochemical plants
  • Oil and gas facilities (refineries, biogas plants)
  • Food and agriculture (grain, sugar, flour, feed)
  • Woodworking and furniture production
  • Metal processing and powder handling
  • Pharmaceutical production
  • Paint shops, coating lines, and printing facilities
  • Waste treatment and recycling plants
What ATEX zones are there?
ATEX zones classify areas based on how often an explosive atmosphere is present. There are gas zones (0, 1, 2) and dust zones (20, 21, 22). This classification helps determine which equipment category and protection level are required for safe operation in each area.
  • Zone 0 / Zone 20: An explosive atmosphere is present continuously or for long periods.
  • Zone 1 / Zone 21: An explosive atmosphere is likely to occur occasionally.
  • Zone 2 / Zone 22: An explosive atmosphere is not expected in normal operation, or only for short periods.
What do ATEX Zone 2 and ATEX Zone 22 mean?
ATEX Zone 2 refers to an area where an explosive gas atmosphere is unlikely during normal operation, and if it occurs, it will exist only for a short time. ATEX Zone 22 is the equivalent classification for combustible dust: an explosive dust atmosphere is not expected in normal conditions, and if it appears, it will be infrequent and short-lived. Both zones represent lower-risk areas but still require equipment certified for the appropriate ATEX category.
Can I use equipment with a higher protection level (EPL) in a lower-classified ATEX zone?
Yes. Equipment with a higher Equipment Protection Level (EPL) can always be used in a lower-risk zone. For example, Gas EPL Gb (Zone 1) can be used in Zone 2. However, lower EPL equipment cannot be used in higher zones.
Can I use equipment certified for a higher gas or dust group in a lower group?
Yes. Equipment certified for a higher gas or dust group can always be used in a lower group. For example, Gas Group IIC is usable in IIB and IIA, but IIA equipment cannot be used in IIB or IIC environments.
What is IECEx and how does it differ from ATEX?
IECEx is an international voluntary certification system based on IEC standards, while ATEX is a mandatory legal framework in the EU. Key differences include:
  • Legal Status: ATEX is mandatory in the EU; IECEx is voluntary but globally recognized.
  • Certification: ATEX allows self-declaration for some categories; IECEx always requires third-party certification.
  • Documentation: ATEX requires CE marking and an EU Declaration of Conformity; IECEx issues a Certificate of Conformity (CoC).
Can I use IECEx-certified equipment in an ATEX installation?
Not automatically. IECEx certification alone is not sufficient to place equipment on the EU market. Equipment must comply with the ATEX Product Directive 2014/34/EU and carry the CE + ATEX marking. However, IECEx certification simplifies the ATEX assessment process since both use similar standards.
Do cables need to be ATEX-certified?
No, cables themselves are not ATEX-certified products and do not carry ATEX markings. However, they must be suitable for use in ATEX installations (e.g., correct temperature resistance, mechanical robustness, chemical resistance) and must be compatible with the ATEX-certified cable gland used.
Why do cable glands need ATEX certification if cables do not?
Cable glands are part of the equipment’s explosion protection concept (e.g., Ex d, Ex e). They perform critical safety functions like maintaining enclosure integrity and preventing ingress. Therefore, they must be tested and certified. Cables do not form part of the protection concept but must match the gland's requirements to ensure the certification remains valid.
What is the difference between Ex d and Ex e cable entries?
Ex d (Flameproof) cable entries must contain an internal explosion and prevent propagation; they require certified flameproof glands (often barrier type) and metallic construction. Ex e (Increased Safety) cable entries must maintain ingress protection and strain relief but do not need to withstand internal explosions. Using the wrong type (e.g., Ex e gland on Ex d equipment) invalidates the certification and is dangerous.