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. 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 hundred measuring points.