Table of Contents
When Does the ATEX Directive 2014/34/EU Apply?
The ATEX harmonized standards are integral to the ATEX Directive 2014/34/EU, which governs equipment and protective systems intended for use in potentially explosive atmospheres. This directive applies when there is a likelihood of gases, dust, or vapors combining with air to form an explosive mixture, necessitating that equipment used in such conditions complies with ATEX.
Industries typically affected include:
- Chemical industry (paint, varnish, solvent production plants),
- Food industry (mills, sugar refineries – large amounts of combustible dust),
- Mining (methane and coal dust hazards),
- Fuel stations (fuel vapors),
- Agriculture (grain silos).
How Does ATEX Relate to the Machinery Directive?
- The Machinery Directive 2006/42/EC primarily regulates general machine safety principles.
- The ATEX 2014/34/EU adds requirements for explosion protection in potentially explosive atmospheres.
Equipment that simultaneously qualifies as machinery and operates in explosive hazard zones must comply with both legal acts – the Machinery Directive and the ATEX Directive. In practice, a manufacturer or importer:
- Conducts a risk analysis according to the Machinery Directive,
- Additionally performs a conformity assessment concerning ATEX requirements if the product will be in an explosive environment.
What Are ATEX Harmonized Standards and Their Benefits?
Presumption of Conformity
The European Union publishes so-called harmonized standards, officially announced in the EU Official Journal. If a manufacturer fully applies a given harmonized standard and documents it appropriately, it is presumed that the product complies with the corresponding essential requirements (in the case of ATEX, the requirements of Annex II of the Directive).
Legal Status and Number of Harmonized Standards
Currently, there are 108 harmonized standards published under the ATEX Directive 2014/34/EU. These include general standards describing design and testing principles, as well as industry-specific or issue-specific standards (e.g., electrical or non-electrical ignition sources).
Examples of ATEX Harmonized Standards
| Standard Number | Short Title | Scope/Remarks |
|---|---|---|
| PN-EN 1127-1:2019-10 | Explosive Atmospheres – Explosion Prevention and Protection – Methodology | Basics of risk analysis and ignition prevention in EX zones |
| PN-EN 60079-1:2014-12 | Explosive Atmospheres – Equipment Protection by Flameproof Enclosures “d” | Specific type of protection against flame propagation |
| PN-EN ISO 80079-36:2016-07 | Non-electrical Equipment for Explosive Atmospheres – Methodology and Requirements | Guidelines for equipment whose main ignition source is not electricity |
| PN-EN 1839:2017-02 | Determination of Explosion Limits and Limiting Oxygen Concentration (LOC) for Gases/Vapors | Useful in hazard analysis, defines ignition parameters of substances |
| PN-EN 14460:2018-02 | Explosion Resistant Equipment | Construction requirements for equipment designed to withstand internal explosions |
These standards describe testing procedures, design guidelines, and methods for documenting compliance. For many engineers and managers, they are essential tools – by referring to a specific standard, they gain a ready set of solutions on how to ensure explosion safety.
ATEX Harmonized Standards: Impact on Conformity Assessment Procedures
When to Involve a Notified Body?
The ATEX Directive introduces various equipment categories (e.g., M1, M2 in Group I or 1, 2, 3 in Group II). Depending on the category, a conformity assessment procedure is selected (e.g., module B+D, B+F, G, internal production control, etc.).
General rule:
- For highest category equipment (e.g., category 1, M1), the intervention of a notified body is almost always required.
- For less stringent categories (e.g., category 3, used in zones where explosive atmospheres rarely occur), it is possible to apply module A (internal production control) without the involvement of a notified body.
How Do Harmonized Standards Facilitate the Procedure?
- Confirmation of Design Solutions – if the equipment is designed according to a harmonized standard (e.g., PN-EN 60079-15 for “n” type equipment construction), the notified body sees that accepted technical solutions have been adopted.
- Transparent Selection of Tests – standards specify methods for testing explosion resistance or flameproof enclosure tightness, eliminating arbitrariness in safety verification.
- Reduced Certification Time – it is easier and faster to demonstrate compliance with the Directive, which means financial savings and a smoother process for companies to bring products to market.
Documents Confirming ATEX Compliance
- EU Declaration of Conformity
- Certificate of Conformity
- Conformity Certificate (e.g., EU type examination certificate)
FAQ: ATEX Harmonized Standards
It depends on the equipment category. If the machine belongs to category 1 (Group II) or M1 (Group I), which is the highest level of protection, the involvement of a notified body (e.g., within module B – EU type examination) is mandatory. In categories with lower requirements (e.g., 3), internal production control (module A) can be used, meaning the manufacturer can conduct the conformity assessment independently, provided specific conditions are met.
Compliance with the Machinery Directive does not automatically mean compliance with ATEX. An additional risk assessment focusing on ignition sources in potentially explosive atmospheres is necessary, along with applying appropriate conformity assessment procedures according to Directive 2014/34/EU. In practice, procedures from both directives are often combined (e.g., risk analysis and implementation of solutions from machine standards, followed by ATEX modules).
Applying a harmonized standard implies a ‘presumption of conformity’ with its corresponding essential requirements. Consequently, in the event of a supervisory authority inspection, the manufacturer does not need to further demonstrate compliance with these requirements, as harmonized standards are accepted throughout the EU. From a technical standpoint, these standards also help shorten and simplify risk analysis and select the best protective solutions.
No. The EU declaration of conformity (formerly known as the EC declaration in older regulations) pertains to finished equipment (or protective systems), confirming their compliance with ATEX and other directives. In contrast, a certificate of conformity is often issued for components that are not standalone equipment but must meet ATEX parameters (e.g., flameproof enclosure elements). Each component sold separately in the EX context should have such a certificate attached.
Primarily, all possible ignition sources – both electrical (unacceptable sparking, short circuits, overheating of components) and non-electrical (friction, impact, static electricity). The characteristics of combustible substances must also be considered: whether they are dust, gases, mists, and their ignition temperatures or explosion limits. Finally, location requirements (equipment category vs. EX zone) must be checked, and it should be determined whether additional safety measures, such as flameproof, intrinsically safe, or emergency ventilation, are necessary.