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Standards for Laboratory Weights



Thomas J. Bruno, Paris D. Svoronos


The following table provides a summary of the requirements for metric weights and mass standards commonly used in chemical analysis1-3. The actual specifications are under the jurisdiction of ASTM Committee E-41 on General Laboratory Apparatus and are the direct responsibility of subcommittee E-41.06 that deals with weighing devices. These standards do not generally refer to instruments used in commerce. Weights are classified according to type (either Type I or Type II) grade (S, O, P or Q) and class (1, 2, 3, 4, 5 or 6). Information on these mass standards is presented to allow the user to make appropriate choices when using analytical weights for the calibration of electronic analytical balances, for making large-scale mass measurements (such as those involving gas cylinders) and in the use of dead weight pressure balances.
CRC Handbook of Chemistry and Physics - 93rd edition
Publisher Info
CRC Taylor Francis, Boca Raton, FL


Bruno, T. and Svoronos, P. (2012), Standards for Laboratory Weights, CRC Taylor Francis, Boca Raton, FL (Accessed March 5, 2024)
Created June 22, 2012, Updated February 19, 2017