OJEU — Official Journal of the European Union

The Official Journal of the European Union (abbreviated OJEU, or in other EU languages: Journal Officiel de l’Union Européenne, Amtsblatt der Europäischen Union) is the daily official gazette of the European Union. It is the sole authoritative source where EU legal acts — regulations, directives, decisions — and official notices acquire legal force, and the only place where references to harmonised standards officially establish their status as conferring presumption of conformity with EU directives.

For hardware engineers, product compliance managers, and anyone working with CE marking and EU product legislation, understanding the OJEU is not optional — it is a fundamental reference in the CE marking workflow.

Key Facts

Structure of the OJEU

The OJEU is divided into two main series, each with distinct content:

L Series (Législation — Legislation)

The L Series contains legally binding acts of the EU:

• Regulations (directly binding in all member states)
• Directives (binding on member states as to the result; require national transposition)
• Decisions (binding on their addressees)
• Corrigenda (corrections to previously published acts)

All EU product legislation that creates CE marking obligations is published in the L Series. Examples:

• Radio Equipment Directive (RED): OJ L 153, 22.5.2014
• Low Voltage Directive (LVD): OJ L 96, 29.3.2014
• Cyber Resilience Act (CRA): OJ L, 20.11.2024
• General Product Safety Regulation (GPSR): OJ L, 23.5.2023

C Series (Communications and Information)

The C Series contains non-binding acts and communications, including:

• References to harmonised standards — the legally significant publication that establishes a standard’s status under EU directives
• Commission notices
• Opinions and recommendations
• Court of Justice decisions (when published)

Critical for CE marking: A harmonised standard (EN 300 328, EN 18031-1, EN 62368-1, etc.) only provides presumption of conformity with a directive when its reference is published in the OJEU C Series. Publication in the OJEU C Series is what officially activates the standard’s legal status under EU directives.

The Role of OJEU in Harmonised Standards

The pathway from a draft standard to a legally recognised harmonised standard involves the OJEU:

1. EU Commission mandates ETSI/CEN/CENELEC to develop a standard
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2. Standards body develops and publishes the standard (ETSI EN, EN, etc.)
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3. Commission evaluates the standard against directive essential requirements
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4. Commission publishes reference in OJEU C Series
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5. Standard now has LEGAL PRESUMPTION OF CONFORMITY status

Without OJEU publication, a standard — even if technically excellent — does not provide legal presumption of conformity. A manufacturer applying a non-referenced standard must still demonstrate conformity against the essential requirements directly.

How to Check OJEU for Harmonised Standards

The Commission publishes lists of harmonised standards by directive in the OJEU C Series. These lists can be found on:

1. EUR-Lex (eur-lex.europa.eu): Search for “Harmonised standards” in the Q&A search or browse the OJ C series.
2. European Commission standardisation pages: Direct links to the latest OJEU references lists for each directive.

Each entry in the harmonised standards list includes:

• Standard reference number (e.g., EN 300 328)
• Standard title
• Publication reference (OJ C issue number and date)
• Date from which the standard was withdrawn (superseded standards)

Transition periods: When a standard is revised (e.g., EN 300 328 V1.9.1 → V2.2.2), the OJEU C notice sets a withdrawal date for the old version and a mandatory date from which only the new version applies. During the transition period, both old and new versions may be used for CE marking.

OJEU and the Withdrawal of IEC 60950-1

A concrete example of OJEU’s practical importance: IEC 60950-1 (IT equipment safety) was withdrawn as a harmonised LVD standard via OJEU C notice, with a transition period ending 20 December 2020. After that date, products certified only to IEC 60950-1 could no longer use it for LVD CE marking — only EN 62368-1 applied. Companies unaware of this OJEU notice faced CE marking compliance gaps.

OJ L Series and Delegated Acts

When the European Commission issues a Delegated Regulation (e.g., Commission Delegated Regulation (EU) 2022/30 — the RED Delegated Act activating cybersecurity requirements), it is published in the OJ L Series. This is where the manufacturer’s obligation arises.

The sequence for the RED Delegated Act:

1. OJ L — Delegated Regulation (EU) 2022/30 published → legal obligation created
2. OJ C — References to EN 18031-1, -2, -3 published → harmonised standard route available
3. Manufacturer applies EN 18031-x → gains presumption of conformity → self-declares

Related Terms

• ETSI — The standards body that develops EN 300 328, EN 303 645, EN 18031, and many other standards referenced in the OJEU.
• CE Marking — The market access mark for which harmonised standards (referenced in OJEU) provide the compliance framework.
• Conformity Assessment — OJEU harmonised standard references determine which assessment module is available.
• RED — One of the key directives whose harmonised standards list is published and maintained via OJEU.
• EN 18031 — Cybersecurity standard whose reference in OJEU creates its legal status under the RED Delegated Act.

Monitoring OJEU for standard withdrawals and new references is a continuous compliance obligation — not a one-time check. A product CE-marked to a standard that is subsequently withdrawn from the OJEU list may need to be re-tested for continued market validity. Inovasense tracks OJEU harmonised standard publications as part of ongoing compliance support for our clients. See our EU compliance services.

Official References

• EUR-Lex — Official Journal of the European Union — EUR-Lex (access all Official Journal issues)