Conformity of measuring instruments

Design and manufacture

Requirements concerning the design and manufacture of measuring instruments consist of the provisions of instrument-specific legislation and standards or standard recommendations. According to the law, a measuring instrument shall be verified and fit for its intended purpose.


Requirements concerning the structure and markings of measuring instruments need to be taken into account in the design of the instrument. Co-operation with Tukes and inspection bodies helps in avoiding wrong decisions. Tukes also supervises the manufacturers of measuring instruments and publishes the requirements that they are subject to. Manufacturers and contractors produce the designed products.


Ensuring the conformity of products is the responsibility of the manufacturer. Depending on the provisions of instrument-specific legislation, inspection bodies can perform a type examination to the measuring instrument and verify its conformity or approve the manufacturer’s quality monitoring procedures.


Placing on the market

A key element in placing a measuring instrument on the market is an assessment of its suitability for purpose. Those acting in different roles in the trade industry need to know the measuring instruments they are selling.


Manufacturers, importers, wholesale dealers and retail businesses can all place measuring instruments on the market.


Purchase, entry into service and use

The operator who uses the measurement results is responsible for using suitable measuring instruments that comply with requirements, and for ensuring that the use of the measuring instrument is monitored and that the instrument’s reliability is verified on a regular basis.


If the seals of the measuring instrument have to be broken when the instrument is being serviced, it has to be verified before it enters into service again, unless the repair shop responsible for servicing is authorised by Tukes to seal instruments.


The EU does not regulate the in-service supervision of instruments – this is made on a national level.


Changing the place of use of a measuring instrument

It is possible to move a measuring instrument to another town, for example. Moving an instrument to another location may require action from inspection bodies in cases where seals have to be broken because of the move or the value of gravitational acceleration in the new location is different from that in the previous location.


Inspection bodies

Inspection bodies approved by Tukes take care of in-service verification of measuring instruments. Under the law, verification of utility measuring instruments – i.e. devices that measure the consumption of water, electricity, gas or heat – may be performed following methods approved by an inspection body. 


Supervisory authorities

Authorities responsible for the supervision of measuring instruments are Tukes and Regional State Administrative Agencies. Market surveillance of measuring instruments is the responsibility of Tukes.


Elsewhere on the Net


  • OIML (International Organization of Legal Metrology)
  • WELMEC (European Cooperation of Legal Metrology)