The International Vocabulary of Terms in Legal Metrology (VIML) is the result of work on the harmonization of terminology used in the field of legal metrology which has been carried out by Poland within the OIML since 1961.

The work was initiated by Professor Jan Obalski who played a leading part in the preparation of the first edition of the Vocabulary of Legal Metrology (VML) which was sanctioned by the 3rd International Conference of Legal Metrology in 1968 and published in 1969.

The first edition was later completed by two addenda sanctioned by the 4th and 5th International Conferences of Legal Metrology in 1972 and 1976 respectively. The second edition of the VML, which included the first edition of 1969 and the two addenda, was published in 1978 as a bilingual French–English version.

The need to harmonize metrological terminology worldwide resulted in the identification of general concepts which form the basic terminology common to various
technical disciplines. Seven International Organizations (BIPM, IEC, IFCC, ISO, IUPAC, IUPAP and OIML) thus jointly prepared the International Vocabulary of Basic and General Terms in Metrology (VIM) for which the VML, 1978 edition, was used as one of the basic sources.

The importance of international aspects of terminology in legal metrology and the need to speak a common language in international cooperation resulted in the continuation of work on the Vocabulary of Legal Metrology although the major part of the text of the 1978 edition had been transferred to the VIM.

The work was restarted in 1995 by OIML TC 1 “Terminology”, Poland being in charge of its Secretariat.

Four subsequent drafts resulted in a text which was discussed at a TC 1 Seminar held in Warsaw in November 1998, followed by a postal inquiry among P-members of TC 1 and postal approval by the CIML in 2000.

The VIML now includes only the concepts used in the field of legal metrology. These concepts concern the activities of the legal metrology service, the relevant documents as well as other problems linked with this activity. Also included in this Vocabulary are certain concepts of a general character which have been drawn from the VIM.

0 BASIC AND GENERAL TERMS IN METROLOGY

All the terms and definitions of the International Vocabulary of Basic and General Terms in Metrology (VIM, second edition 1993) are fully adopted by OIML and applicable in the field of legal metrology.

Therefore, as a general rule, these terms are not repeated in this document unless a specific reference to the VIM is added.

1 BASIC TERMS IN LEGAL METROLOGY

1.1 metrology

science of measurement [VIM 2.2]

1.2

legal metrology

part of metrology relating to activities which result from statutory requirements and concern measurement, units of measurement, measuring instruments and methods of measurement and which are performed by competent bodies

NOTES

1 The scope of legal metrology may be different from country to country.

2 The competent bodies responsible for legal metrology activities or part of these activities are usually called legal metrology services.

1.3

metrological assurance

all the regulations, technical means and necessary operations used to ensure the credibility of measurement results in legal metrology

2 LEGAL METROLOGY ACTIVITIES

2.1

legal metrological control

the whole of legal metrology activities which contribute to metrological assurance

NOTE

Legal metrological control includes:

- legal control of measuring instruments,

- metrological supervision,

- metrological expertise.

2.2

legal control of measuring instruments

generic term used to globally designate legal operations to which measuring instruments may be subjected, e.g. type approval, verification, etc.

2.3

metrological supervision

control exercised in respect of the manufacture, import, installation, use, maintenance and repair of measuring instruments, performed in order to check that they are used correctly as regards the observance of metrology laws and regulations

NOTE

Metrological supervision includes checking the correctness of quantities indicated on and contained in pre-packages.

2.4

metrological expertise

all the operations for the purpose of examining and demonstrating, e.g. to testify in a court of law, the condition of a measuring instrument and to determine its metrological properties, amongst others by reference to the relevant statutory requirements

2.5

type (pattern) evaluation

systematic examination and testing of the performance of one or more specimens of an identified type (pattern) of measuring instruments against documented requirements, the results of which are contained in the evaluation report, in order to determine whether the type may be approved

NOTE

“Pattern” is used in legal metrology with the same meaning as “type”; in the entries below, only “type” is used.

2.6

type approval

decision of legal relevance, based on the evaluation report, that the type of a measuring instrument complies with the relevant statutory requirements and is suitable for use in the regulated area in such a way that it is expected to provide reliable measurement results over a defined period of time

2.7

type approval with limited effect

approval of a type of measuring instrument that is linked with one or more specific restrictions such as:

- the period of validity,

- number of instruments covered by the approval,

- obligation to notify the competent authorities of the place of installation of each instrument,

- use of the instrument

2.8

examination for conformity with approved type

part of the examination of a measuring instrument carried out to ascertain its conformity with the approved type

2.9

recognition of type approval

legal decision taken by a party either voluntarily or based on a bi- or multilateral arrangement whereby a type approved by another party is recognized as complying with the relevant regulatory requirements, without issuing a new type approval certificate

2.10

withdrawal of type approval

decision canceling a type approval

NOTE

The withdrawal is justified in case of:

- alterations of the type,

- circumstances that affect metrological durability and/or reliability,

- effects altering the metrological performance of the instrument required by law and coming to light only after the official type approval was granted.

2.11

conformity assessment of a measuring instrument

testing and evaluation of measuring instruments to ascertain whether or not a single instrument, an instrument lot or a production series of instruments comply with all statutory requirements applicable to this instrument type

NOTE

Conformity assessment does not only concern metrological requirements but also requirements relating to:

- safety,

- EMC,

- software identification,

- ease of use,

- marking, etc.

2.12

preliminary examination

partial examination of certain elements of a measuring instrument of which verification will be completed at the place of installation or an examination carried out before certain elements of the measuring instrument are fitted

2.13

verification of a measuring instrument

procedure (other than type approval) which includes the examination and marking and/or issuing of a verification certificate, that ascertains and confirms that the measuring instrument complies with the statutory requirements

2.14

verification by sampling

verification of a homogeneous batch of measuring instruments based on the results of examination of a statistically appropriate number of specimens selected at random from an identified lot

2.15

initial verification

verification of a measuring instrument which has not been verified previously

2.16

subsequent verification

any verification of a measuring instrument after a previous verification and including:

- mandatory periodic verification,

- verification after repair

NOTE

Subsequent verification of a measuring instrument may be carried out before expiry of the period of validity of a previous verification either at the request of the user (owner) or when its verification is declared to be no longer valid.

2.17

mandatory periodic verification

subsequent verification of a measuring instrument, carried out periodically at specified intervals according to the procedure laid down by the regulations

2.18

voluntary verification

any verification which does not result from the application of obligation

2.19

rejection of a measuring instrument

decision that a measuring instrument does not comply with statutory requirements for verification and prohibiting its use for applications requiring mandatory verification

2.20

recognition of verification

legal decision taken by a party, either voluntarily or based on a bi- or multilateral arrangement whereby a verification certificate issued and/or a verification mark applied by another party is recognized as complying with relevant requirements

2.21

inspection of a measuring instrument

examination of a measuring instrument to ascertain all or some of the following:

- verification mark and/or certificate is valid,

- no sealing marks are damaged,

- after verification the instrument suffered no obvious modification,

- its errors do not exceed the maximum permissible inservice errors

NOTE

Inspection of a measuring instrument may be done only after verification.

2.22

inspection by sampling

inspection of a homogeneous batch of measuring instruments based on the results of evaluation of a statistically appropriate number of specimens selected at random from an identified lot

2.23

marking

affixing of one or more of the marks as described in 3.7, 3.8, 3.9 and 3.10

NOTES

1 Verification and sealing marks may be combined.

2 The manufacturer may be authorized to apply other marks.

2.24

obliteration of a verification mark

cancellation of the verification mark when it has been found that the measuring instrument no longer complies with the statutory requirements

3 DOCUMENTS AND MARKS WITHIN LEGAL METROLOGY

3.1

law on metrology

legal acts and regulations that in particular define the legal units of measurement and prescribe the organizational structure of legal metrology programs and activities

3.2

type approval certificate

document certifying that type approval has been granted

3.3

verification certificate

document certifying that the verification of the measuring instrument was carried out with a satisfactory result

3.4

metrological expertise certificate

document issued by an authorized institution and registered by it, stating the conditions under which the metrological expertise took place and reporting the investigation made and the results obtained

3.5

rejection notice

document stating that a measuring instrument was found not to comply or no longer to comply with the relevant statutory requirements

3.6

documentation of a measurement standard

all the documents attached to or associated with a measurement standard describing its technical and metrological characteristics and indicating the conditions and methods of its conservation, maintenance and use

3.7

verification mark

mark applied to a measuring instrument certifying that the verification of the measuring instrument was carried out with satisfactory results

NOTE

The verification mark may identify the body responsible for verification and/or indicate the year or date of verification or its expiry date.

3.8

rejection mark

mark applied to a measuring instrument in a conspicuous manner to indicate that the measuring instrument does not comply with the statutory requirements and obliterating the previously applied verification mark

3.9

sealing mark

mark intended to protect the measuring instrument against any unauthorized modification, readjustment, removal of parts, etc.

3.10

type approval mark

mark applied to a measuring instrument certifying its conformity to the approved type

4 UNITS AND MEASURING INSTRUMENTS

4.1

legal units (of measurement)

units of measurement required or permitted by regulations

NOTE

Legal units may be:

- SI units,

- their decimal multiples and submultiples as indicated by the use of SI prefixes,

- non-SI units specified by relevant regulations.

4.2

International System of Units, SI

the coherent system of units adopted and recommended by the General Conference on Weights and Measures (CGPM) [VIM 1.12]

4.3

legally controlled measuring instrument

measuring instrument which conforms to prescribed requirements, in particular legal metrological requirements

4.4

measuring instrument acceptable for verification

measuring instrument of an approved type, or one that meets relevant specifications and may be exempt from type approval

4.5

approved type

definitive model or family of measuring instruments permitted for legal use, the decision being confirmed by the issuing of a type approval certificate

4.6

specimen of an approved type

measuring instrument of an approved type, which on its own or together with suitable documentation, serves as a reference e.g. for checking conformity of instruments with the approved type

4.7

verification equipment

equipment that meets the statutory requirements and that is used for verification