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EU Harmonized Standards - What does that mean?

If you can prove - with a conformity assessment - that your product complies with the European (EN) harmonized standards, the "presumption of conformity" applies to your product in the European Union (EU). This means that your product is in line with the corresponding EU rules, directives, and regulations. What this means in detail, and where the difficulties lie today (keyword: James Elliot legal case), is explained in this blog.

The world of technical standards can be confusing. This blog post should help you to understand at least the concept of harmonized EN standards.
The world of technical standards can be confusing. This blog post should help you to understand at least the concept of harmonized EN standards. Credit for the picture:


CEN = European Committee for Standardization. Responsible for European standardization. Together with ETSI (telecommunications) and CENELEC (electrical engineering), it forms the European system for technical standardization.

CENELEC = European Committee for Electrotechnical Standardization. Responsible for European standardization in the area of electrical engineering.

CoC = Data of Cessation

DOW = Date of Withdrawal

EMC = Electromagnetic Compatibility

EMCD = Electromagnetic Compatibility Directive (Directive 2014/30/EU)

EN = European Norm = European Stanard

ETSI = European Telecommunications Standards Institute. Responsible for European standardization for telecommunications, broadcasting, and other electronic communications networks and services

ESO = European Standards Organization (CEN, CENELEC, ETSI)

HAS = Harmoized Standards

OJEU = Official Journal of the European Union. The OJEU is the official publication for EU legal acts, other acts, and official information from EU institutions, bodies, offices, and agencies.

1. Harmonized Standards: Definition and Purpose

Harmonized standards in the context of the European Union (EU) are technical specifications adopted by one of the European standardization organizations, developed in accordance with EU directives and regulations. Products that comply with harmonized standards are presumed to meet the essential requirements of the relevant EU directives and regulations, making the compliance process more straightforward. This presumption of conformity reduces the risk of legal challenges and provides a clear path to demonstrate compliance with EU law.

2. Key Points About EU Harmonized Standards

Development and Adoption:

  • Standardization Organizations: The main bodies responsible for developing harmonized standards are the European Committee for Standardization (CEN), the European Committee for Electrotechnical Standardization (CENELEC), and the European Telecommunications Standards Institute (ETSI).

  • Alignment with Legislation: These standards are created to align with specific essential requirements laid out in EU legislation, particularly directives and regulations concerning product safety and performance.

Citation in the Official Journal of the European Union (OJEU):

  • Legal Effect: When a harmonized standard is cited in the OJEU, it gains a presumption of conformity with the relevant essential requirements of the applicable EU directive or regulation.

  • Presumption of Conformity: Products manufactured in accordance with these cited standards are presumed to comply with the corresponding EU legislation, simplifying the regulatory process for manufacturers.

Voluntary Nature:

  • Optional Compliance: While harmonized standards provide a clear and recognized path to compliance, their use is voluntary. Manufacturers can choose alternative methods to demonstrate that their products meet EU requirements, as long as they can prove equivalence.

CE Marking:

  • Indication of Compliance: Products that meet harmonized standards and essential requirements can carry the CE marking, indicating conformity with EU directives and enabling free movement within the European Economic Area (EEA).

Presumption of Conformity

  • Presumption of Conformity: When a product complies with harmonized EU standards, it benefits from the presumption of conformity. This means that it is automatically assumed to meet the essential requirements of the relevant EU directives and regulations.

Reversal of the Burden of Proof

  • Normal: Normally, the burden of proof lies with the manufacturer to demonstrate that their product meets all applicable legal requirements.

  • Reversal: With the presumption of conformity, the burden shifts away from the manufacturer. Instead, it is up to the regulatory authorities or other challengers to prove that the product does not comply with the essential requirements, despite adhering to the harmonized standards.

3. When does a harmonized EN standard lose its presumption of conformity?

A harmonized European (EN) standard can lose its presumption of conformity under several circumstances:

Withdrawal or Replacement

  • Withdrawal: If a harmonized standard is officially withdrawn by the relevant European standardization organization (CEN, CENELEC, or ETSI), it loses its presumption of conformity. This can happen if the standard becomes outdated or is no longer considered adequate to meet the essential requirements of the relevant EU legislation.

  • Replacement: When a harmonized standard is replaced by a new or revised version, the presumption of conformity shifts to the updated standard. The old standard typically loses its presumption of conformity after a transitional period.

Changes in EU Legislation

  • Amendment or Repeal of Directives/Regulations: If the underlying EU directive or regulation that the harmonized standard supports is amended or repealed, the standard may lose its presumption of conformity. New or revised legislation might require updated standards to ensure continued compliance.

Official Objection by the European Commission

  • Formal Objection: The European Commission or an EU member state can raise a formal objection to a harmonized standard if it is found to no longer meet the essential requirements of the relevant EU directive or regulation. If the objection is upheld, the standard may be revised or withdrawn, leading to a loss of its presumption of conformity.

Judicial or Administrative Decisions

  • Court Rulings: As highlighted in cases like "James Elliott Construction Limited v Irish Asphalt Limited," a court may determine that a product does not comply with essential requirements despite adhering to a harmonized standard. Such judicial decisions can influence the perceived reliability and applicability of a standard.

  • Market Surveillance Actions: If market surveillance authorities find that products conforming to a harmonized standard are unsafe or fail to meet essential requirements, this could lead to a reassessment or withdrawal of the standard.

Lack of Citation in the Official Journal of the European Union (OJEU)

  • Omission from the OJEU: For a standard to confer a presumption of conformity, it must be cited in the OJEU. If a standard is removed from the OJEU, it loses its official status and, consequently, its presumption of conformity.

 Simplified life-cycle of a harmonized EN IEC EMC standard.
Simplified life-cycle of a harmonized EN IEC EMC standard.

4. DOW vs. DoC

The figure above shows the simplified life-cycle of a harmonized EN EMC standard with DOW and DoC. Note: not every EN standard is requested by the European Commission to be harmonized. The Date of Withdrawal (DOW) and the Date of Cessation (DoC) are both important dates in the lifecycle of harmonized EU standards, but they serve different purposes:

Date of Withdrawal (DOW)

  1. Definition: The DOW is the date by which the previous version of a harmonized standard must be formally withdrawn by the European standardization organizations (such as CEN, CENELEC, or ETSI).

  2. Purpose: It marks the end of the transition period during which both the old and the new versions of the standard can be used.

  3. Implications:

  • After the DOW, the old standard is no longer available for use and is officially withdrawn from circulation.

  • Products can no longer be assessed against the withdrawn standard for compliance purposes.

Date of Cessation (DoC)

  1. Definition: The DoC is the date after which the previous version of a harmonized standard loses its presumption of conformity.

  2. Purpose: It marks the end of the period during which products complying with the old standard are presumed to meet the essential requirements of the relevant EU directives and regulations.

  3. Implications:

  • After the DoC, manufacturers must ensure their products comply with the new or revised version of the standard to maintain the presumption of conformity.

  • Products that are still assessed against the old standard after the DoC will no longer be presumed to conform to EU requirements, which can lead to compliance issues.

Key Differences

  1. Function:

  • DOW: Focuses on the withdrawal of the standard itself from use and circulation.

  • DoC: Focuses on the loss of the legal benefit (presumption of conformity) that the old standard provides.

  1. Impact on Compliance:

  • DOW: After this date, the old standard is no longer available for compliance assessment.

  • DoC: After this date, products must meet the new standard to be presumed compliant with EU legislation.

  1. Sequence:

  • Typically, the DOW precedes the DoC. The standard is withdrawn (DOW), and after a certain period, the presumption of conformity provided by the old standard ceases (DoC).

5. Where to find harmonized EMC standards?

Which EMC standards are harmonized for the European Electromagnetic Compatibility Directive (EMCD, Directive 2014/30/EU) are published on this website [1]: link.

6. Why are there no more harmonized EMC EN standards since the James Elliott court case?

To avoid regulatory uncertainty, economic operators and manufacturers of electric and electronic devices push for harmonization of EN standards. Therefore, it is of high interest for the industry to have harmonized EN standards. However, Since the James Elliott case [2], there have been significant challenges regarding the assessment and validation of harmonized standards by HAS consultants for the EMC Directive (2014/30/EU). The figure below shows, that there was so far (May 2024) no positive assessment by the HAS consultants when it comes to harmonized EN EMC standards.

One of the main reasons for the absence of positive assessments is the increased scrutiny and legal uncertainty brought about by the court ruling. The James Elliott decision [2] clarified that harmonized standards, although not legally binding themselves, have a quasi-legal status when cited in the Official Journal of the European Union (OJEU), making their precise compliance critical.

This ruling heightened the need for meticulous alignment of these standards with EU regulations, creating a complex and stringent environment for HAS consultants to operate within. Additionally, the standards need to meet both the technical specifications and the formal requirements set by the EU, which can be an intricate and lengthy process. Consequently, this has led to delays and a backlog in the positive assessment of EMC standards under the Directive 2014/30/EU​ 

Zero positive outcomes of assessments for EMC standards harmonization by HAS consultants [3].
Zero positive outcomes of assessments for EMC standards harmonization by HAS consultants [3].

7. Summary

EU harmonized standards are critical tools for ensuring product compliance with EU legislation. They facilitate market access and enhance product safety while providing legal certainty through the "presumption of conformity" and reducing trade barriers within the EU.

However, since the Court's ruling in James Elliott, the harmonization of EN EMC standards has stalled and it is not clear whether this will improve in the near future.

About the Author

Reto Keller is a principal electronic development engineer and is currently president of the Academy of EMC. Furthermore, he is a committee member of the IEC TC 65/SC 65A/WG4 (EMC standard IEC 61326-2-6).

Reto Keller
Reto Keller


[1] European Commission. Summary list of titles and references of harmonized standards under Directive 2014/30/EU for EMC. [2024-June-11]

[2] InfoCuria. Case-law. C-613/14 - James Elliott Construction. [2024-June-11]

[3] CEN and CENELEC. European Harmonized Standards: A Journey from Legal Framework to Citation in the OJEU. [2024-May-23]


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