A program for conformity assessment of the calibration results with the specification

Abstract

This paper describes the procedure for calculating the conformance probability of the results of the calibration with the
requirements or specifications (standards or manufactures), including borderline cases. An original program created in Excel was
presented, which makes it easy to calculate in a Metrology Laboratory. During the development of this program, the recommendations
of the European Accreditation Team (EA), as well as the requirements of ISO / IEC 17025: 2017, were taken into account. The goal of
this program is to provide the customer with a certificate of calibration with the declared uncertainty as well as the compliance of the
results of the calibration with the requirements or specifications. The program was developed for the needs of the Metrology
Laboratory, which is located in the company ORAO a.d. Bijeljina. The accreditation body at the accreditation examination of the
Metrology Laboratory checked the results of the program. The international standard ISO 10576-1: 2003 describes the procedure for
calculating the conformance probability of the calibration results with the specification. According to the described procedure, each
calibration result must first be graphically presented according to normal PDF (Gaussian distribution). Then, in order to determine the
probability of occurrence of any measured value, use the z-value and the standard surface tables below with normal PDF. In metrology
laboratories, this is a difficult and long-lasting process because the digital multimeter can be calibrated at even a hundred measuring
points.