Updated Uncertainty Analysis for a Flowmeter Calibration Process Part 1: Transfer Standards

A transfer standard for flowmeter calibration provides traceability to a primary standard. It is typically used for most commercial calibrations because it represents an economically attractive alternative to a primary system. A set of critical flow venturi (CFV) transfer standards have been maintained in calibration at CEESI for the past 35 years. The uncertainty in mass flowrate has been estimated to be ±0.5% at 95% level of confidence based on analysis of the components that contribute uncertainty. This paper presents analysis of historical data that supports a lower estimate of uncertainty.