Rationale

Section 16.1 requires the user to take at least 3 measurements for verification and allows up to 2 measurements to be discarded at the user’s discretion. This means that an instrument can pass verification with only one measurement. One measurement is not sufficient to determine the accurate function of an instrument. Furthermore, an average of several measurements can still read in tolerance even if all the individual measurements are outside of the calibrated test block value. This ballot item increases the minimum number of measurements to 5 and adds an additional tolerance requirement for the range of the measurements.