Understanding ATEX Harmonised Standards: What 'State of the Art' Really Means for Manufacturers

For many manufacturers, achieving ATEX certification feels like the finish line, a signal that a product is ready for production, marketing and sale within the European Union. But certification is not the end of the journey. ATEX compliance is dynamic, evolving in line with new knowledge, updated standards and shifts in accepted engineering practice. 

This continual evolution is known as the ‘state of the art’, and understanding it is essential for any organisation placing equipment or protective systems into potentially explosive atmospheres. As standards change, so too does the benchmark against which safety, performance and conformity are judged. 

This article explains what the ‘state of the art’ means within the ATEX Directive, how harmonised standards support it, how updates to those standards may affect existing certificates, and what practical steps manufacturers should take to remain compliant. 

 

What Is the ‘State of the Art’? 

Within ATEX (Directive 2014/34/EU), the ‘state of the art’ represents the current, accepted level of technical knowledge and safety performance expected to meet the Essential Health and Safety Requirements (EHSRs). It is not about adopting the latest experimental solutions or investing in unnecessarily complex technologies. Instead, it reflects what experts, from regulators to industry specialists, consider reasonable, appropriate and effective for mitigating ignition risks. 

The state of the art evolves through several channels, including: 

• Harmonised standards published in the Official Journal of the European Union (OJEU) 

• Lessons learned from incidents and testing insights 

• Technological advancements 

• Consensus from Notified Bodies, standardisation groups and technical committees 

As this collective knowledge shifts, so does the expectation placed on manufacturers. A product fully compliant with yesterday’s standards may not meet today’s state of the art, even if its design has not changed. 

 

What Are ATEX Harmonised Standards? 

Harmonised standards are the most visible and practical mechanism for demonstrating ATEX compliance. When manufacturers design and assess their products against a harmonised standard listed in the OJEU, they benefit from presumption of conformity. This means authorities accept that the product meets specific EHSRs unless proven otherwise. 

Standards such as those in the EN 60079 and EN 80079 series provide detailed requirements for design, testing, documentation and marking for explosion‑protected equipment. These standards undergo revision roughly every five to seven years. 

Each revision includes: 

• A publication date 

• A withdrawal date (after which the previous edition no longer grants presumption of conformity) 

Once a standard is withdrawn, manufacturers relying on older editions risk falling out of compliance. Even minor design or documentation assumptions tied to outdated editions may no longer align with the state of the art. 

 

How Do Changes to Standards Affect the ‘State of the Art’? 

Not all updates to standards affect compliance in the same way. 

 

Editorial or minor changes 

These clarifications or corrections rarely impact product safety or design. In such cases, manufacturers typically need only to update documentation to reference the latest edition. 

 

Major technical changes 

These have more significant consequences. They may include: 

• Revised or newly defined fault conditions 

• Updated test methods 

• Changes to thermal or mechanical requirements 

• New creepage and clearance distances 

• Enhanced marking or labelling expectations 

Major changes often reflect a shift in risk understanding. When this occurs, the state of the art moves, and products designed to older requirements may no longer be considered compliant without reassessment or redesign. 

 

When a standard remains unharmonised 

A unique challenge arises when CENELEC publishes a new edition, but it is not yet harmonised into the OJEU. This situation has become more common in recent years, creating a gap between industry expectations and legal presumption of conformity. 

During this period: 

• The older OJEU‑listed edition still grants presumption of conformity. 

• The newer unharmonised edition may better represent current safety expectations. 

To address this, the European Coordination Group of ATEX Notified Bodies (ExNBG) discusses and collectively recognises which standards represent the current state of the art, aiming for consistency across Notified Bodies. 

 

What Does This Mean for Existing Certification? 

ATEX certificates are not static. They reflect the state of the art at the time of issue. As standards change, underlying assumptions about safety change with them.

 

Products still being manufactured 

Each product placed on the market must comply with requirements valid at the time of placement—not the standards in force when the product was originally certified. If a newer standard introduces safety‑critical changes, relying solely on an older edition is not acceptable. Manufacturers must reassess their products, potentially requiring redesign, retesting or certificate updates. 

 

Products already installed 

For equipment already in service, the Directive generally does not require retroactive upgrades. However: 

• Replacement parts must not compromise explosion protection. 

• Changes in risk understanding may mean certain spares require reassessment. 

• Manufacturers or Notified Bodies may be asked to justify why an existing product still aligns with the state of the art. 

 

Practical Steps Manufacturers Should Take 

Ensuring ongoing ATEX compliance requires structure, vigilance and proactive controls. Manufacturers should: 

1. Monitor standards continuously

Assign clear responsibility for tracking applicable standards, editions and withdrawal dates. Maintain a standards register for each product line. 

2. Conduct gap analyses on new editions

Whenever a standard is updated, compare the new and previous editions to understand the impact. Identify whether the changes are editorial or safety‑critical. 

3. Engage early with your Notified Body

Early discussions help avoid production delays, unexpected testing needs or certification issues. 

4. Maintain robust technical documentation 

Ensure technical files, risk assessments, test reports and user instructions are consistently updated to reflect current expectations. 

5. Control design changes

Evaluate all design modifications, however small, to determine their impact on explosion protection and certification.

 

ATEX certification is not a one‑off achievement. It is a commitment to maintaining compliance throughout a product’s life cycle, in line with the evolving state of the art. As standards change and new knowledge emerges, manufacturers must stay informed, engaged and proactive. 

By monitoring standard developments, conducting meaningful assessments, collaborating with Notified Bodies and maintaining strong change‑control processes, you can ensure your products remain safe, compliant and trusted, today and into the future.