Foreword

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This document was prepared by Technical Committee ISO/TC 48, Laboratory equipment.

This second edition cancels and replaces the first edition (ISO/TR 20461:2000), which has been technically revised and cancels ISO/TR 20461:2000/Cor 1:2008.

The main changes are as follows:

— the term “standard deviation of the mean delivered volume” has been replaced in this document by “repeatability” according to ISO/IEC Guide 99 ;
— a new uncertainty calculation example has been supplied;
— new uncertainty components have been added, namely, reproducibility, air cushion and resolution;
— a new Annex A concerning approaches for the estimation of uncertainty in use of a single delivered volume has been added;
— a new Annex B concerning volume correction due to pressure changes has been added.

Any feedback or questions on this document should be directed to the user’s national standards body. A complete listing of these bodies can be found at www.iso.org/members.html.

PD ISO/TR 20461:2023

Determination of uncertainty for volume measurements of a piston-operated volumetric apparatus using a gravimetric method

Current

Published:

28 Feb 2023