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# Introduction  
# Mutual Acceptance Arrangement - MAA  
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OIML Mutual Acceptance Arrangement (MAA)

Frequently Asked Questions (FAQs)


1. What is the MAA?

The MAA is a framework document which establishes the rules for signing Declarations of Mutual Confidence (DoMC) related to categories of measuring instruments.


2. What is a Declaration of Mutual Confidence (DoMC)?

A Declaration of Mutual Confidence is a declaration signed by various bodies in charge of legal metrology activities in different countries, by which they declare that they will voluntarily accept test results of type evaluations conducted according to the OIML specifications and possibly additional specifications. A DoMC concerns a specific category of instruments, therefore there will be different DoMCs for the various categories.


3. What is an OIML Test Report?

An OIML Test Report is a report drawn up according to the Test Report Format specified in the relevant Recommendation. This report gives:

  • the results of the tests carried out during the type evaluation,
  • the results of the examinations conducted during the type evaluation,
  • a conclusion as to whether the instrument tested complies with the requirements.

The OIML Certificate of Conformity is issued on the basis of this OIML Test Report.

The OIML Test Report is issued under the responsability of the Issuing Authority since it includes the conclusions of the type evaluation (whether the type meets the requirements or not ).

In the revision of OIML B3 OIML Certificate System for Measuring Instruments, the "OIML Test Report" will be renamed "OIML Evaluation Report".

This Evaluation Report may include several test reports issued by different laboratories if several laboratories have participated in examining and testing the measuring instrument.

If issuing a national type approval requires additional tests and examinations, an additional report may be established. This additional report is called a "Complete Evaluation Report". It includes the OIML Evaluation Report and the test reports related to the relevant additional tests and examinations.


4. Who are the participants in a DoMC?

There are Participants (Member States) and Associates (Corresponding Members).

Two types of participants may be distinguished:

  • a Utilizing Participant,
  • an Issuing Participant.

An Issuing Participant is an OIML Issuing Authority which issues OIML Certificates. These Certificates validate OIML Test Reports. An Issuing Participant is also a Utilizing Participant.

A Utilizing Participant will accept OIML Test Reports validated by OIML Certificates but will not issue any OIML MAA Tests Report or OIML MAA Certificate under the DoMC.

A Utilizing Participant may be either a National Issuing Authority, or a National Responsible Body, or an OIML Issuing Authority.

Associates (from OIML Corresponding Members) are similar to Utilizing Participants but do not participate in the Committee on Participation Review (CPR).


5. Who will pay the participation fees?

The participation fees are due by the Issuing Participants in a DoMC, when they have submitted an application (accompanied by a complete file) according to 4.9 of OIML B 10. These fees are due for the examination of the candidacy of an Issuing Authority. Utilizing Participants will not have to bear these participation fees.

These fees were approved at the 12th International Conference of Legal Metrology. For the amounts, please refer to the synthesis of CIML decisions related to the MAA, available under the heading "General Documentation".


6. What will be the binding character of participants' signatures?

There is no legally binding obligation to respect such a signature, and no dispute on this matter will be ever brought before a court of law.

But one can be relatively confident that no one will sign if he does not intend to respect his obligations. A signatory who did subsequently not accept test results without serious reasons would be expelled from the DoMC and his reputation would suffer from this.

This system is voluntary; nobody is obliged to sign DoMCs, but this is a guarantee of good cooperation.


7. Is it legal for a national body to sign a DoMC?

Yes, it is legal in all countries, as far as is known.

When a national body declares that he intends to accept other bodies' test results, this does not give other bodies legal authority in the country. When serious reasons arise which lead to rejection of the results of a given test report, then it is acceptable that the participant does not accept them. The test reports and Certificates issued by other countries' participants have no legal status in the country.

Each participant maintains his legal authority and responsibility at national level.


8. Will legal metrology bodies be obliged to participate?

Of course not: as mentioned above, this is a voluntary system.

This being said, all national legal metrology bodies are encouraged to participate in this system. Several reasons may be put forward to show the importance of participating:

  • For countries who signed the Technical Barriers to Trade Agreement (World Trade Organization), this Agreement urges them to participate in such systems,
  • Participants in a DoMC will benefit from being permanently informed of the latest technologies and from being made aware of the technical knowledge of other participants,
  • Participants in a DoMC will indirectly benefit from the availability of other participants' facilities, especially when they do not have such facilities themselves,
  • For bodies who operate in a competitive market, it would be a commercial handicap not to participate in DoMCs.

9. What does the application file have to contain?

  • An official letter confirming participation in the MAA and the type of participation (Issuing Participant or Utilizing Participant for each category);
  • The most recent internal audit report according to ISO/EIC Guide 65 using the Checklists (OIML B 10);
  • A certificate of accreditation covering the scope of the DoMC, if applicable;
  • Evidence, if applicable, that this accreditation has been delivered by a National Accreditation Body which an ILAC-MRA signatory;
  • Information about the type testing capabilities (Annex C of OIML B 10);
  • A list of subcontracting testing laboratories indicating, for each one, which tests it performs;
  • The certificates of accreditation of the subcontracting testing laboratories, if applicable,
  • The most recent internal audit report of each subcontracting testing laboratory according to ISO/CEI 17-025 using the Checklists (OIML B 10),
  • The results of intercomparisons, if applicable,
  • Information about additional tests and examinations required for national type approval, if applicable,
  • A copy of the most recent OIML Test Report(s) issued for the considered category(ies).

10. What do "Accreditation" and "Intercomparisons" mean in Annex C of OIML B 10?

Annex C of OIML B 10 is a questionnaire about testing capabilities.

These testing capabilities and, more generally Accreditation and Intercomparisons, are related to type evaluation tests according to the relevant OIML Recommendations.


11. Will sending an application mean that the applicant commits itself to signing a DoMC when finalized?

We must remain very flexible about this process. Sending an application means that the Issuing Authority envisages signing a DoMC, but is not a commitment to sign it.

In the process of development of a DoMC, a number of issues will be discussed. A potential participant can disagree with the conclusions of the CPR and decide to remain outside the DoMC at least for the time being.

The CPR set up before the signature of a DoMC will be a provisional CPR, and any Member of it may decide to withdraw once the DoMC is finally signed. The "final" CPR will be composed of representative of signatories after the DoMC is signed.

However, we can assume that sending in an application means that the potential participant does wish to sign the DoMC, and moreover that hopefully he will sign it.


12. Who shall be assessed by peer assessment?

An Issuing Authority (Issuing Participant in the DoMC) and/or a subcontracting Testing Laboratory which performs type evaluation examination and/or testing, and which is not accredited for those type evaluation tests and examinations as specified by the identified clauses of the applicable OIML Recommendations, shall be assessed by peer assessment.

The CPR will examine the scope of peer assessment when an Issuing Authority or a subcontracting Test Laboratory is accredited only for one category (e.g. NAWI type evaluation tests) and applies to be an Issuing Participant in the other category too (e.g. Load Cells). The type of tests and the metrological characteristics (e.g. measuring range) under the scope of the accreditation and the similarity of tests and of testing facilities between the two categories will be taken into account.