Interlaboratory system to ensure and improve the quality of glassware calibration and use in a large laboratory.

This paper describes the implementation and methodology of an interlaboratory system that ensures the quality of glassware calibration and use in a large laboratory. The interlaboratory system involves periodic comparisons between laboratories with evaluations and improvements made over time. Two similar items are calibrated in each exercise according to a detailed calibration procedure. The reference value is traceable to the international system supplied by a metrology laboratory. The results are evaluated as normalized errors and analyzed by Youden graphs. The calibration procedure is presented. An interlaboratory experiment is described in which 7 participating laboratories performed calibrations of 2 volumetric flasks. The reported results, the interlaboratory evaluation, and the actions taken are presented.