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Any discrepancies or differences that may arise in translations of the official Portuguese versions of these materials are not binding and have no legal effect for compliance or enforcement purposes.

Decree Law No. 71/2011

Publication: Republic Diary No. 115/2011, Series I of 2011-06-16
  • Issuer: Ministry of Economy, Innovation and Development
  • Diploma Type: Decree Law
  • Number: 71/2011
  • Pages: 3201 - 3243

Summary in plain english

What is it?

This decree-law establishes the standards to be met by the following measuring instruments:

  • water meters
  • gas meters and the devices used to correct measurements when needed (conversion devices)
  • active electrical energy meters (for instance, the devices used to measure the electricity consumption in a house)
  • heat meters (for instance, the devices used to measure the heat consumption in a house)
  • measuring systems for continuous and dynamic measurement of quantities of liquids, except for water (for instance, petrol pump meters)
  • automatic weighing instruments (for instance, dispensers for filling olive oil or wine packages)
  • taximeters (cab fare meters)
  • material measures (for instance, a measuring tape or a beaker marked in millilitres)
  • dimensional measuring instruments (for instance, the devices used to measure the length of materials like rope or to measure the area of an irregularly shaped object, like a piece of leather)
  • exhaust gas analysers.
What will change?
Marking to show an instrument complies with legislation

Measuring instruments can only be sold and used in the European Union if they have the CE marking and the metrology marking.

The CE marking is a label by which the manufacturer ensures that an instrument complies with European standards. It is granted after an evaluation performed by an independent body, which verifies if the measurements given by the instrument are reliable.

The metrology marking is a specific label for measuring instruments and is placed next to the CE marking. It is formed by the letter “M” followed by the last two digits of the year it was placed on the instrument (for instance, M11 for a marking placed in 2011).

Instruments previously approved may be placed on the market

If an instrument has already been approved according to the criteria established by decree-law 291/90, it may be sold and used until:

  • the expiry date of the approval, if there is one
  • 30 October 2016, if the approval does not have an expiry date.

After these dates, the instruments may be sold and used only after being assessed using the criteria established by this decree-law.

Instruments should not exploit the allowed margins of error

All the instruments of measurement have a margin of error allowed by law. However, that margin of error may not be used to always favour one of the parties involved in the transaction. For instance, a taximeter has a margin of error of 0.1%, but this should sometimes benefit the cabdriver and sometimes the client.


The Authority for Economic and Food Safety (ASAE) monitors the compliance of these rules.

If these are not followed, manufacturers may have to pay the following fines:

  • 1 000 to 3 740 euros, if they are individuals
  • 2 500 to 44 890 euros, if they are companies.

If an instrument, even with the proper markings, does not comply with the criteria set out in this decree-law, ASAE may prohibit or restrict its sale or take it off the market.

Accreditation of the bodies that evaluate the instruments

The bodies that assess the measuring instruments have to be accredited by the Portuguese Accreditation Institute (IPAC) within 24 months of this decree-law coming into effect.

The list of accredited bodies is sent to the European Commission by the Portuguese Institute for Quality.

What are its benefits?

This decree-law is intended to:

  • unify all the legislation relating to these measuring instruments, making it simpler, transparent and easy to use
  • defend the interests of consumers, ensuring that the measurements are reliable.
When does it come into effect?

This decree-law comes into effect the first day of the month after being published.

Original Version


  • Legal translator is the translation of texts within the field of law


Legislative consolidation integrates the various amendments and rectifications made into an original legal diploma in order to make its consultation more accessible to the citizen.