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Análisis · 2026-10-03

Measuring instruments, approval at the factory and verification after it

The last article in this series turns to an abstract object of regulation, namely whether something measures correctly. That also makes measuring instruments the one category where the regulator is not finished when the product ships.

The regulated object is accuracy

Water meters, electricity meters, gas meters, weighing instruments, fuel dispensers: what these have in common is that they produce nothing and only report how much. So the mandatory requirements are not about safety but about accuracy, meaning under which conditions, with what tolerance, and how that tolerance is demonstrated.

That creates a structure unique in this series: regulation does not stop at the factory gate. A weighing instrument is compliant when placed on the market, and whether it is still accurate two years later is a different regime, the one covering verification or calibration. A buyer asking only whether a certificate exists misses the second half.

EU: two directives running in parallel

EU measuring instruments split into two lines. The Measuring Instruments Directive, MID 2014/32/EU, covers the instruments subject to legal metrology control, and its method is to sort by instrument type into annexes, where the designations read as MI-001 and MI-003 among others, each with its technical requirements and conformity route.

Non-automatic weighing instruments sit on their own under 2014/31/EU, whose text states that it applies to all non-automatic weighing instruments. An ordinary electronic price-computing scale normally travels this route rather than the MID.

Both were published on 29 March 2014, at OJ L 96/149 and L 96/107 respectively, and both are recasts, which is worth noting because older directive numbers in this field are often mixed up with them. A notified body takes part in assessment, and the CE mark plus metrology marking is applied afterwards. The marking carries the year and the notified body number, so the marking itself tells you when the assessment happened.

The EU is amending it, and three dates mean three different things

The MID was amended in 2026 by Directive (EU) 2026/706. It repays reading on its own, because three dates appear together and each means something different.

The date of adoption, 11 March 2026, appears in the closing formula as done at Strasbourg on 11 March 2026. That is when the legislators signed; it is neither the date of entry into force nor a duty on businesses.

The date of publication is 20 March 2026 in the Official Journal. Entry into force follows the standard formula, on the twentieth day after publication, which works out to 9 April 2026, and the reference in the text to Directive 2014/32/EU as amended on 9 April 2026 corroborates it. Note that this one is derived rather than written as a literal date.

Then the national dates: member states must adopt the necessary measures by 10 April 2028 and apply them from 10 October 2028. Instruments placed on the market under the previous rules before that date benefit from transitional arrangements, and certificates issued under the previous rules remain valid until 10 April 2038 at the latest.

Put the three together and they restate the discipline this series keeps returning to. When reading the dates in a regulation, establish first who the subject of that line is: the legislature, the Official Journal, a member state, or a manufacturer.

US: the handbook is not binding until a state adopts it

One part of the US system is easily misread. NIST Handbook 44 sets out the specifications, tolerances and technical requirements for commercial weighing and measuring devices, but it is not itself federal mandatory law. The obligation comes from state adoption: once a state's metrology law takes the relevant content of the handbook into its own requirements, it binds locally. Type evaluation follows the same logic, recognised through a national type evaluation programme run with the state metrology authorities.

So a US measuring instrument question should ask which edition the target state has adopted and whether the instrument has passed type evaluation, rather than whether a federal certificate exists. This is the same structure as in machinery, PPE, construction products and cables. In this series the US has shown the same pattern five times: no national product passport, with the obligation arising from who adopts what.

For this section we hold the regime only. We have NIST's entry page but not the handbook text, so the claim that force comes from state adoption is marked unverified in our traceability record.

China: verification is the heart of it

The centre of gravity in China is mandatory verification. Measuring instruments used for trade settlement, safety protection, medical care and environmental monitoring fall under a mandatory verification catalogue, must pass verification before use, and must be re-verified on a set cycle. Manufacturing such instruments separately requires type approval. Some measuring instruments also sit inside the CCC catalogue, which is a different instrument again.

This layer is the least familiar to a foreign buyer. A product passing factory testing does not mean it can be used in China, because use requires verification. We have not collected the texts here, meaning the articles of the metrology law, the verification regulation numbers and the catalogue scope, so the page states the structure and no numbers.

Japan, Korea, Brazil, Australia-NZ, Gulf

Japan regulates under its metrology act, with verification and type certification for specified instruments. Korea works through type approval and verification under its metrology act. Brazil applies INMETRO metrology certification with conformity to metrological technical regulations. Australia and New Zealand manage type approval under the national measurement legislation, with periodic verification handled by the states. The Gulf states regulate under the GSO metrology technical regulation, with Saudi Arabia routing through SABER.

For these markets we currently hold the regime described but no primary text, so the page states the regime and no document numbers.

Ten markets side by side

Two columns, what entry controls and whether anything follows entry:

The second column is the point of this article. Not one of the ten markets stops regulating at the factory gate. They differ only in who performs verification, how often, and what happens if it is skipped, and those three things are rarely asked at the purchasing stage even though they decide whether the instrument can be used on site at all.

What to ask before you order

Ask four things about measuring instruments: which regime governs it in the target market, a MID annex or the weighing instruments directive; which entity holds the type approval or type evaluation, and under which number; what else the marking carries beyond CE, since the metrology marking includes a year and a body number that can be read; and who performs verification once it is in use, and on what cycle.

The fourth question is where this article differs from the other thirteen. Everywhere else in this series, compliance is largely settled by the time the goods leave the factory. With measuring instruments it is not. Whether an order succeeds can depend on someone getting the instrument verified after it is installed. To work through these in order, start with the free verification checklist. The previous article in this series is wires and cables; the series opens with toys, which is the best place to start if you have come in partway. To see how certifications and verifications are recorded, look at a report sample, or get in touch.