Knowledge from the field of proficiency testing and comparative measurement

"Evaluation of the performance of a participant according to previously established criteria by comparisons between laboratories" (DIN EN ISO/IEC 17043:2010).

The performance of a measurement or test task by several (at least 2), independent laboratories. The results of the different laboratories are compared and evaluated by the provider of the test. The goal is to determine the performance of the participants under equal conditions. In this way, the laboratories are given the opportunity to prove their competencies or to identifysources of error as well as potential for improvement. 

Testo Industrial Services is a DIN EN ISO/IEC 17043:2010 accredited provider of proficiency tests and comparative measurements in the thermodynamic and dimensional environment. Our current scope of accreditation can be found in our accreditation certificate.   

Suitability tests and comparative measurements can also be carried out within a non-accredited framework in accordance with the current service portfolio of our calibration laboratory. We make no distinction in terms of methodology between accredited and non-accredited proficiency tests and comparative measurements. Both cases follow the requirements of DIN EN ISO/IEC 17043:2010.

In the future, we plan to expand our accreditation portfolio as a provider of proficiency testing and comparative measurements with additional measurement parameters and measuring equipment.

Ring comparison:

Proficiency tests are often also referred to ring comparisons/ring tests. Within an ring comparison/ring test, a specific measurement or test task is carried out by a group of laboratories independently of each other and one after the other. There are ring-shaped and star-shaped forms.

Testo Industrial Services is the provider responsible for planning and organizing proficiency tests and comparative measurements. In addition to the coordination on time, content and technical issues, the evaluation, using statistical methods and reporting, is also carried out by the provider.

The pilot laboratory is responsible for the characterisation of the calibration items and carries out the intermediate tests. In addition, it can set the reference value.

Qualifications:

• Many years of experience in the measurand of the calibration object
• Accreditation for the corresponding calibration object and the procedure with the intended scope

Responsibilities:

• Stability and homogeneity tests
• Carrying out the intermediate examination

For example, accredited testing and calibration laboratories as well as testing and calibration laboratories seeking accreditation can take part. It is important that the participants can carry out the calibration according to the required procedures and that the measurement result has a measurement uncertainty according to EA-4/02:2022. As the performance criterion is the EN value by default.

The participation in proficiency tests and comparative measurements is mandatory for accredited laboratories in accordance with DIN EN ISO/IEC 17025. These comparisons represent an important element for the validation of calibration procedures and results in the quality management of a laboratory and offer an external method for quality assurance of the measurement procedures.

Within the proficiency tests and comparative measurements , identical test equipment is analysed by different laboratories according to the same specifications. As a provider, Testo Industrial Services compares the measurement results obtained and makes statements about the general measurement uncertainty and the quality of the measurements of all participants.

Proficiency tests and comparative measurements are used in the following cases: 

• Quality assurance of laboratory tests and measurements
• Verification of the measurement uncertainty of a measurement method
• Comparison of calibration processes with other laboratories
• Compliance with the requirements according to DIN EN ISO/IEC 17025:2018
• Proof of competence towards customers, superiors and authorities

Testo Industrial Services always offers different proficiency tests and comparative measurements, which are carried out in a ring-shaped manner. Individual bilateral settlements are also offered. Make a note of our upcoming proficiency tests or comparative measurements now or request a bilateral comparison.

Proficiency tests and comparative measurements