Guia Ilac-G24

GUIDANCE

ILAC-G24

INTERNATIONAL

SERIES

Edition 2007 (E)

DOCUMENT

OIML D 10
Edition 2007 (E)

Guidelines for the determination of calibration
intervals of measuring instruments

Guide pour la détermination des intervalles de calibration
des instruments de mesure

INTERNATIONAL
LABORATORY

ORGANISATION INTERNATIONALE
DE METROLOGIE LEGALE

ACCREDITATION
COOPERATIONINTERNATIONAL ORGANIZATION
OF LEGAL METROLOGY

ILAC-G24:2007 / OIML D 10:2007 (E)

CONTENTS

Copyright – ILAC .................................................................................................................................. 3
Foreword – OIML.................................................................................................................................. 4
Preamble ................................................................................................................................................. 5
Purpose ................................................................................................................................................... 5
Authorship.............................................................................................................................................. 5
1. Introduction ............................................................................................................................... 5
2. Initial choice of calibration intervals ......................................................................................... 7
3. Methods of reviewing calibrationintervals .............................................................................. 7
Method 1: Automatic adjustment or “staircase” (calendar-time) ...............................................8
Method 2: Control chart (calendar-time) ................................................................................... 8
Method 3: “In-use” time............................................................................................................ 9
Method 4: In service checking, or “black-box” testing ............................................................. 9
Method 5: Other statistical approaches ..................................................................................... 9
Bibliography......................................................................................................................................... 11

2

ILAC-G24:2007 / OIML D 10:2007 (E)

Copyright (ILAC)
ILAC-G24:2007
© Copyright ILAC 2007

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