Revision of EURAMET Calibration Guide No. 19 'Guidelines on the Determination of Uncertainty in Gravimetric Volume Calibration'

Project Description

The aim of this project is to improve some ambiguities within the existing Calibration Guide No. 19 (Guidelines on the Determination of Uncertainty in Gravimetric Volume Calibration, version 3.0, 09/2018), to include some missing topics (e.g. scale calibration), to improve evaluation of some uncertainty contribution and to give calibration procedures for volume measuring instruments that do not have calibration procedures defined in relevant standards.

For an overview of EURAMET's Calibration Guidelines, please go here >>

Final Report 2026-11-03

Since the previous report, the working group has held a total of three online meetings.
These sessions facilitated further improvements and refinements to the calibration guidelines. The following updates have been implemented:

• Equation Formatting: All equations throughout the document have been standardized using the MathType equation editor, ensuring consistency in presentation and readability.
• Expanded Calculation Examples: The guidelines now include two detailed calculation examples. In addition to the existing example for a volumetric flask, a new example has been added for a pycnometer, providing broader applicability and practical insight.
• Clarification and Refinement of Text: Several sections of the guidelines have been revised to improve clarity and descriptiveness, enhancing the overall comprehensibility of the document.
• Symbol Uniqueness: Indices in the symbols of certain equations have been updated to ensure that all symbols are unique and unambiguous.
• External Influences on Calibration: Additional text and references have been incorporated to address influences on calibration originating from external documents, thereby strengthening the traceability and robustness of the methodology.
• Updated References: References to external sources have been reviewed and updated to reflect the most current and relevant literature.
• Measurement Uncertainty Evaluation: In alignment with EURAMET Calibration Guide No. 21, the evaluation of measurement uncertainty due to unknown temperature of the instrument being calibrated has been revised based on more realistic assumptions.

Inclusion of Statistical Parameters:

Also following EURAMET Calibration Guide No. 21, a recommendation has been added to include the standard deviation of calibration results and the number of repeated measurements in the calibration certificate.

For an overview of EURAMET's Calibration Guidelines, please go here >>

Progress Report 2025-03-11

Since the last report, the team has convened in two online meetings. Several enhancements and updates have been made to the guidelines:

• The text in certain sections of the guidelines has been improved and refined, making it more descriptive and clearer
• Indices in the symbols of some equations have been updated to ensure the symbols are now unique
• Additional text and references have been added concerning the influences on calibrations that originate from external documents
• References to external sources have been updatedFollowing the EURAMET Calibration Guide No. 21, the evaluation of measurement uncertainty due to the unknown temperature of the instrument being calibrated has been revised to be based on a more realistic assumption
• Similarly, based on the EURAMET Calibration Guide No. 21, a recommendation has been added to include the standard deviation of the results obtained during calibration, as well as the number of repeated measurements performed, in the calibration certificate

Progress Report 2024-05-08

We have set goals that the revision must address. Related tasks have been distributed among members of the revision group. Progress was presented at the Volume Subgroup at the TC-Flow meeting in Kajaani Finland. Some new goals were established there, primarily the division of the existing guideline into two guidelines (separate guideline for calibration and determination of uncertainty at gravimetric volume calibration for proving tanks, overflow pipettes and standard test measures).

At the meeting, two new members of the Subcommittee (PTB, Germany and DKD, Germany) expressed interest in joining the revision group, which was has been accepted.