MID – Measuring Instruments Directive

The abbreviation MID stands for the term "Measuring Instruments Directive" and is the equivalent of the German term "Messgeräte-Richtlinie". This refers to the measuring instruments directive 2004/22/EC of the European parliament and the council dated the 31st March 2004.

What are the aims of the MID?

  • EU-wide regulation of the market access of respective measuring devices
    • Creation of a harmonised European market for measuring devices
    • Uniform approval process for all EU states and individual additional states - Single, uniform approval testing
    • Uniform, cross-border specification for first calibration
  • Uniform product labelling
  • Reduction of tests and test costs
    • First calibration takes place through a manufacturer's declaration of conformity
    • Separate calibration testing and calibration fees omitted
    • Reduced delivery times
  • Equality in competition due to high requirements for product quality
    • Additional requirements regarding precision in the small load range - Higher EMC requirements
    • Improved picture of the latest measuring technology status

What does MID regulate?

The MID applies to 10 types of measuring device (electricity meters, water meters, gas meters, etc.) in the fields of statutory metrology, and defines fundamental and measuring device-specific requirements.

A conformity evaluation process – whereby the cooperation of a notified body chosen by the manufacturer is prescribed – replaces the previous first calibration by the calibration authority or the state-certified test centre.

It transfers the responsibility for first circulation and first commissioning within the EU to the manufacturer. After this, national law applies.

The manufacturer must select one of the conformity evaluation processes prescribed in the MID, through which they guarantee the compliance of the measuring device with the MID under the supervision of a notified body. Only then is it permissible to put the measuring device - compliant with the MID - into circulation or into operation. A declaration of conformity must be supplied with the meter.This is frequently printed in the operating manual.

Following circulation or commissioning of the measuring device, the responsibility for attaining accurate measuring results passes to the user.

  • Labelling the devices

    The sequence of MID labelling is prescribed and must comply with the following example:


The MID has no effect on re-calibrating according to calibration regulations. Measuring devices, whose conformity has been specified in a prescribed conformity evaluation process and which are correctly labelled, are deemed in German to have been initially calibrated.

The measuring device user is once again responsible for submitting a timely application for re-calibration.

The duration of calibration validity is stipulated in the national calibration ordinance. In Germany, this is a period of eight years after MID labelling in the case of electronic electricity meters.

Further information applicable to Germany can be found under the following link: www.eichamt.de