Legal metrology and your scale

Legal metrology rules determine which measuring instruments must be approved and who may inspect them. For scales, it comes down to the following.

What the rules cover

European directive 2014/31/EU is implemented in national law in each country. It requires that a non-automatic weighing instrument used for trade, tariffs, medical weighing, the pharmacy, medical and pharmaceutical analyses and prepackages must be approved and marked: the green M mark. The rules also make whoever uses such an instrument responsible for keeping it compliant, and require an instrument to be re-verified after a repair to the weighing technology.

For prepackages there is also the average quantity system: see the e-mark on prepackages.

Who oversees it

Oversight lies with the national enforcement authority - in the UK, Trading Standards - which carries out checks at businesses that work with verified instruments. An instrument that does not comply may no longer be used, and the user risks a fine. The inspection itself is carried out by notified bodies and approved verifiers.

No fixed re-verification interval, but a duty

Unlike some countries, the rules do not always prescribe periodic re-verification. That does not mean verification lasts forever: the instrument must be within its tolerances at all times, and that is the responsibility of the user. In practice you therefore have it checked periodically, and have it re-verified as soon as the weighing technology has been worked on, a seal has been broken or a check shows too large a deviation. A calibration certificate is the evidence that you are meeting that duty.

What we do

Weighing Experts is authorised by KERN, Adam, OHAUS, Baxtran and Gram to repair and recalibrate their instruments, with original parts. We supply scales verified from the factory - the initial verification is carried out by the manufacturer - and for existing scales re-verification is arranged through the manufacturer; calibration and repair we carry out at your site or in our workshop. See also calibration, repair and re-verification.

In Belgium

In Belgium the same European directive applies, but the national rules differ: periodic re-verification is compulsory and the inspection runs through the FPS Economy and approved inspection bodies. For our Belgian customers we arrange verification and re-verification with the manufacturer.

Frequently asked questions

How often does my scale need to be re-verified?

Where the law sets no interval, re-verification is required after a repair to the weighing technology or a broken seal, and you must make sure the instrument is always within its tolerance. A periodic check with a certificate is the usual way to demonstrate that.

What happens during an inspection by the authorities?

The inspector checks whether the instrument has the green M mark and intact seals and whether it weighs within its tolerance. If it does not comply, you may no longer use it until it has been re-verified, and a fine may follow.

Do the legal-for-trade rules also apply to a market stall or online shop?

Yes. Wherever the customer pays for the weight weighed, including at the market, at the door and when weighing out orders for an online shop.

May a scale without the green M mark stand in a shop?

Only if it is not used to charge customers, for example for portioning in the kitchen. At the counter it is not permitted.