Are Individual Current-Meter Ratings Necessary?

Price current meters used by the Geological Survey are calibrated individually at the National Bureau of Standards. Calibration data for three groups of meters from three different manufacturers were studied to determine the feasibility of continuing this practice. No significant difference was found between the standard error of individual ratings and the standard error of an average rating for a group. New standards for the manufacture, calibration, and use of Price current meters are proposed.