Harmonised standards

Last reviewed: October 2026 · Sources listed at the end of this page.

A harmonised standard is a European standard adopted by one of the three European standardisation organisations — CEN, CENELEC, or ETSI — on the basis of a request from the Commission for the application of Union harmonisation legislation (Regulation (EU) No 1025/2012, Article 2(1)(c)). Once its reference has been published in the Official Journal of the European Union, applying it produces a presumption of conformity with the essential requirements of the relevant EU harmonisation legislation that the standard is designed to cover. The presumption is rebuttable but practically decisive: products built in compliance with a harmonised standard are treated as conforming unless evidence to the contrary is produced.

Harmonised standards are voluntary to use, although the EU Court of Justice has held that a cited harmonised standard forms part of EU law (Case C-613/14 James Elliott Construction; Case C-588/21 P Public.Resource.Org). A manufacturer is free to demonstrate conformity by alternative means, provided it can show that the essential requirements are met. In practice, where a harmonised standard exists for a relevant essential requirement, departing from it requires a documented justification and equivalent technical evidence in the technical file.

Legal basis

• Regulation (EU) No 1025/2012 on European standardisation — defines harmonised standards (Article 2(1)(c)) and sets out the procedure for Commission requests and OJEU publication (Articles 10 and 11).
• Each sectoral act — typically in an Article titled "Presumption of conformity" — confirms that products complying with a harmonised standard, the reference of which has been published in the OJEU, are presumed to conform to the essential requirements covered. Examples: Article 12 of Directive 2014/35/EU; Article 13 of Directive 2014/30/EU; Article 8 of Regulation (EU) 2017/745 (MDR); Article 20(1) of Regulation (EU) 2023/1230 (Machinery).

How a harmonised standard comes into existence

The process under Regulation 1025/2012:

1. Commission standardisation request (formerly called "mandate"). The Commission issues a request to CEN, CENELEC, or ETSI to develop a standard covering specified essential requirements. The request defines scope, deliverables, and deadlines.
2. Standard drafting by a Technical Committee of the standardisation organisation, with national experts and stakeholder participation. Drafts are circulated for national member-body voting.
3. Adoption and publication by the standardisation organisation as an EN standard (e.g., EN 60204-1, EN ISO 12100).
4. Commission assessment against the standardisation request and the essential requirements. The Commission may accept, reject, or accept with restrictions or notes.
5. Implementing decision published in the OJEU under Article 10(6) of Regulation 1025/2012, listing the reference of the standard with its dated edition, the act it covers, and any restrictions on the presumption of conformity.
6. National transposition by member bodies (DIN, NF, BSI, UNI, etc.), each publishing the standard as its national version with the same dated edition.

Only after step 5 — publication of the reference in the OJEU — does the standard produce a presumption of conformity. A CEN or CENELEC EN standard whose reference has not been published in the OJEU is a voluntary standard like any other; it does not trigger the presumption.

Where to find the references

The Commission publishes consolidated lists of harmonised standards by act on its Single Market portal:

• Harmonised standards (Commission) — entry point.
• Each act has its own page (e.g., harmonised standards for the Low Voltage Directive, for EMC, for Machinery, for Toys).
• The authoritative legal reference remains the OJEU implementing decision. Commission summary pages are convenience tools; the OJEU citation is what triggers the presumption.

References must be checked at the time of conformity assessment, because they are updated regularly. A standard withdrawn from the OJEU list ceases to confer presumption of conformity from the date specified in the implementing decision, which may allow a transition period.

Machinery Regulation: are harmonised standards cited yet?

No, not as of 31 October 2026. Official Journal records to 30 October 2026 show no implementing decision citing harmonised standards in support of Regulation (EU) 2023/1230. All machinery citations remain under Directive 2006/42/EC, in Implementing Decision (EU) 2023/1586.

That list has an end date. Implementing Decision (EU) 2026/2015 (published 7 September 2026) updated it and also repeals it with effect from 20 January 2027, the day the Regulation replaces the Directive. A citation under the Directive therefore does not carry over: under Article 20(1) of the Regulation, the presumption depends on references published for the Regulation. Trade sources report that the Commission intends to cite standards under the Regulation before that date, but we found no official confirmation of the timing.

What this means in practice:

• Placing on the market before 20 January 2027: the Directive and the 2023/1586 citations apply.
• From 20 January 2027: check whether references under the Regulation have been published. Without one, a standard can still be used as a technical specification, but gives no presumption, and the file must show how each requirement is met.
• Annex I, Part B machinery: Module A depends on harmonised standards or common specifications covering all relevant requirements (Article 25(3)). Without them, a Notified Body route is needed.

See the machinery transition guide.

Types of harmonised standards

Machinery safety standards, unlike harmonised standards generally, are classified into three types, described in the introduction to EN ISO 12100 and in ISO/TR 22100-1:

• Type A — Basic safety standards. Cover fundamental concepts and general design principles applicable to all categories of products in a sector. Example: EN ISO 12100:2010 (safety of machinery — general principles for design — risk assessment and risk reduction).
• Type B — Generic safety standards. Cover one safety aspect or one safety-related device usable across a wide range of products. Examples: EN ISO 13849-1:2023 (safety-related parts of control systems); EN ISO 13857:2019 (safety distances to prevent hazard zones being reached by upper and lower limbs).
• Type C — Product-specific safety standards. Cover detailed safety requirements for a specific machine or category of machines. Examples: EN ISO 10218-2:2025 (industrial robot applications and robot cells), EN 415-3:2021 (form, fill and seal machines).

Type C standards take precedence over Type A and B for the products they cover, where the same hazard is addressed. Where no Type C standard exists, the manufacturer relies on Types A and B, supplemented by other technical solutions. Editions above are as listed under Directive 2006/42/EC in Implementing Decision (EU) 2023/1586 at September 2026.

What the presumption of conformity covers and what it does not

The presumption is limited to the essential requirements that the harmonised standard is designed to cover. A standard may not address every essential requirement of an act applied to a product. A general household-appliance safety standard, for example, is read together with the product-specific part for the appliance concerned.

OJEU publication may impose explicit limitations. The implementing decision for a standard often contains restrictions, such as:

• "This publication does not give a presumption of conformity with the essential requirement set out in [specific point of the Annex]";
• Date restrictions: the presumption applies only for products placed on the market from a specified date;
• Notes drawing attention to specific clauses of the standard that do not align with the essential requirements.

These restrictions must be read alongside the standard. A manufacturer cannot claim presumption of conformity for requirements explicitly excluded by the OJEU note.

Applying a harmonised standard "in full" vs "in part"

Some acts make the choice of conformity assessment module conditional on whether harmonised standards are applied in full. The clearest example is the Machinery Regulation:

• Article 25(3) of Regulation (EU) 2023/1230 — for machinery in Annex I, Part B, the manufacturer may use Module A (self-declaration) only if the machinery is designed and built to harmonised standards or common specifications covering all relevant essential health and safety requirements. Otherwise, Module B + C, Module H, or Module G is required. For the six Part A categories, Module A is never available.

"Application in full" means every clause of the standard relevant to the product is implemented. Partial application — where the manufacturer applies some clauses and substitutes others — produces a presumption only for the clauses applied. Where a standard is applied in part, the technical documentation must specify the parts applied (Decision 768/2008/EC, Annex II, Module A, point 2).

When no harmonised standard exists

For some essential requirements, no harmonised standard has been published in the OJEU. The manufacturer must then demonstrate compliance through alternative technical means and document this in the technical file. Acceptable alternatives include:

• Other European or international standards not yet harmonised (e.g., IEC, ISO, EN standards without OJEU reference).
• National standards of EU Member States.
• Technical specifications from authoritative bodies.
• The manufacturer's own technical specifications, supported by design calculations, tests, and risk analysis.

None of these confer the presumption of conformity. The burden of demonstrating compliance with the essential requirements lies entirely with the manufacturer, and the technical file must contain the supporting evidence.

Common specifications

Several recent acts allow the Commission to adopt "common specifications" via implementing acts where harmonised standards are insufficient or absent. Examples: Article 9 of Regulation (EU) 2017/745 (MDR); the Machinery Regulation 2023/1230 (Article 20(3)). Common specifications produce a presumption of conformity in the same way as harmonised standards, by reference to the Commission's implementing act.

Withdrawal and revision

Standards are revised periodically by the standardisation organisations. When a new edition is published:

• The Commission assesses the new edition and may publish its reference in the OJEU.
• The same implementing decision normally provides for cessation of the presumption of conformity for the previous edition, often after a transition period set in that decision.
• During the transitional period, either edition may be applied. After cessation, only the new edition produces the presumption.

A product placed on the market under the predecessor edition before cessation continues to benefit from the presumption it had at the moment of placing on the market — the presumption attaches to the product at that moment, not to ongoing sales.

Common errors

• Citing EN standards not published in the OJEU. EN ISO 9001 is an EN standard, but it is not a harmonised standard for any CE act. Citing it on the Declaration of Conformity as evidence of conformity with essential requirements misrepresents its legal status.
• Citing standards without the dated edition. "EN ISO 13849-1" without edition is ambiguous; "EN ISO 13849-1:2023" identifies the edition. Where amendments are cited with a standard, they are part of the reference.
• Ignoring OJEU restrictions. An OJEU note that excludes a particular clause from the presumption applies regardless of the manufacturer's intent. Citing the standard without the note is a partial citation.
• Confusing CEN-CENELEC harmonised with ISO/IEC international. ISO 9001 is international, not European. The EN ISO version is the European adoption; only EN ISO references published in the OJEU under a specific act produce the presumption.
• Treating absence of a harmonised standard as a regulatory gap. The absence of a standard does not mean an essential requirement does not apply. The manufacturer still must demonstrate conformity by other means.
• Citing withdrawn standards. A standard whose presumption has ceased may still be technically valid but does not produce the legal effect. The OJEU consolidated lists must be checked at the time of conformity assessment.

Worked example

A manufacturer placing a mains-powered pillar drill on the EU market in October 2026 assesses it against Machinery Directive 2006/42/EC, the EMC Directive 2014/30/EU and the RoHS Directive 2011/65/EU. The Low Voltage Directive's safety objectives apply through the machinery requirements, not as a separate act.

It might apply: EN ISO 12100:2010 (Type A) for risk assessment; EN ISO 13849-1:2023 (Type B) for safety-related control functions; EN 12717:2001+A1:2009 (Type C, drilling machines); the applicable EMC standards; and EN IEC 63000 for RoHS documentation. Each reference is checked against the current implementing decision for each act. Where a standard is applied in part, the parts applied are recorded in the technical file. For units placed on the market from 20 January 2027, the check must be repeated under Regulation (EU) 2023/1230.

Frequently asked questions

Are there harmonised standards for the Machinery Regulation yet?

No, not as of 31 October 2026. All machinery citations remain under Directive 2006/42/EC in Implementing Decision (EU) 2023/1586, which is repealed from 20 January 2027. A presumption under Regulation (EU) 2023/1230 needs a reference published for the Regulation.

Are harmonised standards mandatory?

No. They are voluntary, but a manufacturer that does not use them must show by other means that the essential requirements are met. In some cases the choice affects the conformity assessment route, as under Article 25(3) of the Machinery Regulation.

Where is the list of harmonised standards?

On the Commission's harmonised standards pages, by act, with the Official Journal implementing decisions as the legal reference. NANDO lists Notified Bodies, not standards.

Does following an ISO or IEC standard give a presumption of conformity?

Not on its own. Only the European version whose reference is published in the Official Journal under the relevant act does.

Sources

• Regulation (EU) No 1025/2012 on European standardisation — EUR-Lex.
• European Commission — Harmonised standards portal — single-market-economy.ec.europa.eu.
• Commission Implementing Decision (EU) 2023/1586 on harmonised standards for machinery in support of Directive 2006/42/EC — EUR-Lex; amended and repealed from 20 January 2027 by Implementing Decision (EU) 2026/2015 — EUR-Lex.
• Court of Justice of the EU, Case C-613/14 James Elliott Construction — EUR-Lex; Case C-588/21 P Public.Resource.Org, 5 March 2024 — EUR-Lex.
• Regulation (EU) 2023/1230 (Machinery), Articles 20 and 25 — EUR-Lex.
• Directive 2014/35/EU (Low Voltage), Article 12 — EUR-Lex.
• Commission Notice — Blue Guide 2022, Section 4.1.2 — EUR-Lex.