Tolerance micropipet

Table 2-5 lists tolerances for micropipets from one manufacturer. As internal parts wear out, both precision and accuracy can decline by an order of magnitude. In a study17 of 54 micropipets in use at a biomedical lab, 12 were accurate and precise to <1%. Five of 54 had errors >10%. When 54 quality control technicians at four pharmaceutical companies used a properly functioning micropipet, 10 people were accurate and precise to <1%. Six were inaccurate by >10%. Micropipets require periodic calibration and maintenance (cleaning, seal replacement, and lubrication) and operators require certification.18... 

Tolerances given by ASTM Standard E193-94 1999) Standard Specification for Laboratory Glass Micropipets, West Conshohocken, PA American Society for Testing of Material, 1999. 

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