MetrD - Directive 2009/34/EC

What MetrD is and why it matters

The Metrology Directive (MetrD) — formally Directive 2009/34/EC relating to common provisions for both measuring instruments and methods of metrological control — is the EU’s framework law for legal metrology. It does not regulate a single category of instrument. Instead it sets the common provisions, definitions and procedural building blocks that the more specific instrument directives rely on. If you make or place measuring instruments subject to legal metrological control on the EU market, MetrD is the horizontal text that defines how the EU approval and verification mechanism is supposed to work.

MetrD matters because it codifies the shared machinery of EU metrological control: EC pattern (type) approval, EC initial verification, and the markings and symbols that show an instrument has passed those stages. Rather than letting each Member State run an entirely separate national regime, the Directive provides a common scaffold so that approval and verification carried out in one Member State are recognised across the Union. It is the framework on which the more detailed sector directives — notably the Measuring Instruments Directive (MID) and the Non-automatic Weighing Instruments Directive (NAWI) — are built.

📄 Official text: Directive 2009/34/EC on measuring instruments and methods of metrological control — on EUR-Lex →

Who MetrD applies to

MetrD is a framework directive, so its relevance is felt across the chain that brings measuring instruments to market and into lawful use:

Manufacturers of measuring instruments — anyone who makes instruments and methods of metrological control that fall within the categories covered by the EU metrology framework. They are the actors who seek EC pattern approval and present instruments for verification.
Authorised representatives and importers — those who place instruments from outside or within the Union on the market and rely on the common approval and verification provisions to do so lawfully.
National metrology and market surveillance authorities — the bodies in each Member State that grant pattern approvals, carry out or oversee initial verification and apply the recognised markings.
Downstream users in regulated trade — businesses that use instruments in applications subject to legal control (for example weighing or measuring goods for sale) depend on the instruments having passed the framework’s approval and verification steps.

The Directive concerns instruments and methods of metrological control as identified through the EU metrology framework; it works alongside, and is given effect by, the specific instrument directives rather than replacing them.

Key dates and timeline

2009 — Directive 2009/34/EC was adopted as a codified version, consolidating the long-standing common-provisions framework for measuring instruments and methods of metrological control into a single, clearer text.
As a codifying directive, 2009/34/EC brought together the earlier framework provisions without changing their substance, so the underlying EU metrological control mechanism it expresses has applied continuously since the original framework was established.
Because it is a directive, MetrD takes effect through national transposition: each Member State implements its provisions in domestic metrology law, which is then administered by national authorities.

Core requirements

EC pattern (type) approval

A central pillar of MetrD is EC pattern approval — the approval of the design, or type, of a measuring instrument. Pattern approval confirms that an instrument of a given type meets the applicable metrological requirements, allowing instruments of that pattern to proceed to verification. The Directive sets out the common provisions for how approval is granted, what it certifies and how it is documented, so that an approval issued under the framework carries recognised meaning across the Union rather than being confined to one national market.

EC initial verification

Where pattern approval addresses the design, EC initial verification addresses individual instruments. Initial verification is the check that a particular instrument, as manufactured, conforms to the approved pattern and meets the metrological requirements before it is put into use. MetrD provides the common provisions governing this verification step, establishing it as the second stage of the framework’s control mechanism. Together, pattern approval and initial verification form the two-stage backbone of EU metrological control under the Directive.

Markings and symbols

MetrD ties approval and verification to markings. Instruments that have received EC pattern approval and passed EC initial verification carry the corresponding signs and marks that signal their status to authorities and users. These markings are part of the common provisions precisely so that the same evidence of conformity is understood the same way in every Member State. The Directive’s approach to marks and symbols underpins the recognisability that makes mutual recognition workable.

A common framework for the specific directives

Perhaps the most important practical requirement of MetrD is structural: it provides the shared definitions, procedures and provisions on which the specific instrument directives build. Sector legislation such as the MID and the NAWI Directive sets the detailed metrological and technical requirements for particular instrument categories, while MetrD supplies the common metrological-control architecture they sit within. For a manufacturer, this means MetrD is rarely read in isolation — it is the horizontal text you consult to understand the approval-and-verification logic, then applied through whichever specific directive governs your instrument.

Obligations by role

Manufacturers — design instruments to meet the applicable metrological requirements, obtain EC pattern approval for the type, present instruments for EC initial verification and ensure the correct markings are applied.
Authorised representatives and importers — ensure the instruments they place on the market carry valid approval and verification status under the framework and the relevant specific directive.
National authorities — administer pattern approval and initial verification, apply and recognise the markings, and conduct market surveillance within their territory.
Users in regulated trade — use only instruments that hold the required approval and verification status for legally controlled applications.

Enforcement

MetrD is enforced through the national metrology systems of the Member States, which transpose and administer its common provisions. National authorities grant pattern approvals, oversee initial verification, apply the recognised markings and carry out market surveillance of instruments in use. In Denmark, the Danish Safety Technology Authority (Sikkerhedsstyrelsen) is the competent authority responsible for legal metrology.

Because the Directive’s purpose is mutual recognition, approval and verification performed in one Member State are intended to be accepted across the Union, which reduces duplicated control for compliant manufacturers. Conversely, instruments lacking the required approval, verification or markings can be barred from legally controlled use, and the practical specifics of conformity assessment are typically engaged through the applicable specific directive (MID or NAWI). The qualitative reality for a manufacturer is that the framework only delivers cross-border recognition if every stage — approval, verification and marking — is correctly completed.

Getting compliant

Identify whether your instrument is subject to legal metrological control and which specific directive (MID, NAWI or another) governs it.
Treat MetrD as the framework text for the approval-and-verification logic, and apply the detailed requirements of the relevant specific directive.
Obtain EC pattern (type) approval for the instrument design where required.
Present individual instruments for EC initial verification before they enter legally controlled use.
Apply the correct markings and symbols showing approval and verification status.
Keep documentation of approval, verification and conformity available for national authorities.
Monitor for changes in the specific directives and national transposition that affect your instruments.

How Conphora helps

Conphora monitors MetrD together with the specific instrument directives that build on it, and maps your measuring instruments against the relevant requirements. The platform flags gaps in pattern approval, initial verification and markings before they become enforcement problems, helps you generate and keep the right documentation, and alerts you when the framework or its specific directives change so your compliance stays current.

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Sources and further reading

This guide is for general information and is not legal advice.

Last updated: 12 June 2026