BRIEFING
〈31〉 Volumetric Apparatus. This proposal is based on the version of the chapter official as of November 1, 2020. The General Chapters—Measurement and Data Quality Expert Committee is proposing the following revised chapter. On the basis of comments received, the previous proposal that appeared in PF 49(5) [Sep.–Nov. 2023] has been canceled and replaced with this new proposal.
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Clarify that a calibration temperature of 27° C is also performed in other countries that have adopted that reference temperature. Temperature correction might be required when ambient temperature differs from the reference temperature.
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Calibration of volumetric apparatus is needed to ensure the degree of precision required. Frequency of calibration is risk-based and defined in the user’s manual quality management system.
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Incorporate reference to the new chapter Use and Calibration of Volumetric Apparatus 〈1331〉 to provide theoretical bases for calibration and examples.
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Provide alternatives when the limits of error are not met or not suitable at the conditions of use.
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Add a new Table 1 to categorize the volumetric apparatus accuracy classes and the applicable external updated references.
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Update terminology to the International Vocabulary of Metrology [VIM; (Joint Committee for Guides in Metrology, JCGM) 200] for consistency with equivalent public standards, for example, the section Standards of Accuracy formerly containing “capacity tolerances” is proposed to be changed to Limits of Error (or maximum permissible errors). Limits of error has been defined.
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Introduce considerations for piston-operated volumetric apparatus (POVA) in several paragraphs when appropriate. The limits of error for POVAs are included in new columns added to pipettes in Table 3 (0.5 mL) and burettes in Table 4 (5 mL).
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For plastic volumetric apparatuses, introduce temperature correction and equilibration, as well as limits of error.
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Specific references to applicable ISO and American Society for Testing and Materials (ASTM) standards were introduced in the tables for limits of error.
Additionally, minor editorial changes have been made to update the chapter to current USP style.
(GCMDQ: Y. Liu)
Case ID—SUB-1412