INTERNATIONAL RECOMMENDATION
OIML R 34
Edition 1979 (E)
Accuracy classes of measuring instruments
Classes de précision des instruments de mesurage
OIML R 34 Edition 1979 (E)
ORGANISATION INTERNATIONALE DE MÉTROLOGIE LÉGALE INTERNATIONAL ORGANIZATION OF LEGAL METROLOGY
Foreword
The International Organization of Legal Metrology (OIML) is a worldwide, intergovernmentalorganization whose primary aim is to harmonize the regulations and metrological controls applied by the national metrological services, or related organizations, of its Member States. The two main categories of OIML publications are: • International Recommendations (OIML R), which are model regulations that establish the metrological characteristics required of certain measuring instruments and whichspecify methods and equipment for checking their conformity ; the OIML Member States shall implement these Recommendations to the greatest possible extent; International Documents (OIML D), which are informative in nature and intended to improve the work of the metrological services.
Cooperative agreements are established between OIML and certain institutions, such as ISO and IEC, with theobjective of avoiding contradictory requirements; consequently, manufacturers and users of measuring instruments, test laboratories, etc. may apply simultaneously OIML publications and those of other institutions. International Recommendations and Inter-national Documents are published in French (F) and English (E) and are subject to periodic revision. This publication – reference OIML R 34 (E), edition1979 – which is under the responsibility of TC 3 Metrological control, was sanctionned by the International Conference of Legal Metrology in 1972. OIML publications may be Organization’s headquarters: obtained from the
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OIML Draft Recommendations and Documents are developed by technical committees or subcommittees which are formed by the Member States. Certain international and regionalinstitutions also participate on a consultation basis.
Bureau International de Métrologie Légale 11, rue Turgot – 75009 Paris – France Telephone: 33 (0)1 48 78 12 82 and 42 85 27 11 Fax: 33 (0)1 42 82 17 27 E-mail: [email protected] Internet: www.oiml.org
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Accuracy classes of measuring instruments
CHAPTER I 1 General
1.1. Scope 1.1.1. This Recommendation lays down the principles for theclassification of measuring instruments according to their accuracy. 1.1.2. The measuring instruments to which this Recommendation applies are : – material measures, – measuring instruments, – measuring transducers, where these instruments are intended for use in conditions in which errors due to inertia are negligible in relation to the maximum errors laid down for them. 1.1.3. The requirements ofthis Recommendation are not mandatory for zero indicating instruments, or for equipment especially designed for measuring by multiple reading of the indications and for determining the measurement results as the arithmetic mean of several observations. The Recommendation need also not apply to measuring instruments intended to reproduce, convert or measure quantities linked simultaneously to severalparameters, if different maximum errons have to be fixed for these instruments (eg measurement generators cathode ray oscilloscopes) in accordance with these parameters. 1.2. Principles of classification according to accuracy 1.2.1. The classification of measuring instruments according to their accuracy is to be effected by drawing up classes characterizing different levels of accuracy forinstruments of the same category.
Note:
The Reporting Secretariat C.3 ‘Accuracy classes of measuring instruments’ is the consultative body of the Organization responsible for co-ordinating the OIML Recommendations on the classification of measuring instruments according to their accuracy.
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For each accuracy class of one category of instruments, the parameters and characteristics, which…