Accredia / Reference materials / Metrological traceability, calibration and reference materials

Metrological traceability, calibration and reference materials

19 March 2019

From the issue of the first SIT qualification report to a metrological laboratory 40 years have passed, and today there are 189 operators accredited by Accredia to calibrate measuring instruments and equipment and to produce reference materials.

In a tech-dominated world, metrological traceability is as decisive as ever, to ensure that measuring instruments and equipment are always accurate and reliable. The Calibration Laboratories Department of Accredia is responsible for providing and disseminating metrological traceability by verifying competence and issuing accreditations to laboratories and reference materials producers. Let’s talk about these activities with the Director Rosalba Mugno.


The Calibration Laboratories Department has been operating within the National Accreditation Body since 2010, collecting the heritage of the Italian Calibration Service (SIT), which since the 1970s has been working to qualify metrological laboratories, called Centers by virtue of accreditation obtained. Today, what types of operators do you accredit?

The Department verifies and guarantees the competence of calibration laboratories and reference material producers, that are managed by following two different evaluation and accreditation ways, in terms of procedures and processes, starting from different standards providing the requirements, respectively the UNI CEI EN ISO/IEC 17025 and the UNI CEI EN ISO 17034.

Accredited operators issue certificates of reference materials or, in case of samples and instruments, calibration certificates on the market. Certificates issued under accreditation are therefore used not only by other testing and calibration laboratories, and by certification, inspection and verification bodies, but also by the end users – industry or single consumer – to ensure that the equipment has an adequate error with respect to its intended use.


Also in the field of metrological traceability accreditation has acquired an increasingly important role over the years, with a consequent increase in both the requests for calibration certificates and the number of accredited laboratories to issue them on the market. What is the measure of this trend?

From 2010-2012, years in which there were 2 or 3 accredited laboratories per year, we have reached an increase of 10 laboratories a year, up to 189 operators in 2018, of which 5 are also accredited as reference material producers. A positive trend, which obviously corresponds to a significant increase in the number of certificates issued in the area, almost 150 thousand at December 31 last year.

The increase is caused on one hand by the general greater request for calibration certificates, on the other hand by the emergence of new types of certificates following the introduction of non-traditional instruments, such as the spectrum analyzer or the particle counter, used in sectors such as those for the control of exhaust gases or fine dust. Requests are also recorded for individual types of customized instruments, for example those with which the profile rails are surveyed, the optical instruments and those for speed detection. All instruments that must guarantee the highest possible level of reliability.

Over the years, therefore, with the same requests for accreditation for the instruments used in traditional activities, those for new-generation instruments are growing, introduced thanks to the advancement of technology. Finally, in 2018, the increase is also due to the expansion of the scope of competence of calibration laboratories, stated by the Ministerial Decree 93/2017, for the periodic verification of measuring instruments in the fiscal sphere, or by the Ministerial Decree 282/2017 for speed cameras, which have recognized and formalized the accreditation obligation.


A particular category of operators for the reliability of measurement results is that of the reference materials producers. The Department has recently reorganized their accreditation, but the activity has been intense since the beginning. Can you tell us about the most important steps?

2018 is a year that marks the history of reference materials. At the end of this year the last decisive step towards the ratification of the existence, also in Italy, of reference materials producers (RMPs) accredited according to the international standard UNI CEI EN ISO 17034:2017 was completed. First, the producers were accredited according to the ISO Guide 34. This accreditation, although of national value, did not meet the rules of free movement on the international market. With the introduction of the harmonized ISO standard, these application limits have fallen.

Published in 2016, the ISO 17034 standard establishes a 3-year transition period, which will end in November of this year, within which the reference materials producers must adapt to the new rules set for accreditation. The Italian situation is positive: of the 5 accredited producers, 4 have already passed to ISO 17034; the fifth one is in advanced stage of transition.

The production of reference materials (RMs) and, among them, of certified reference materials (CRMs) is now carried out in compliance with an internationally recognized standard, and accreditation of reference material producers soon will benefit of the extension of Mutual Recognition Agreements at European level (EA MLA) and worlwide (ILAC MRA). An important result for Accredia, the third accreditation body which, together with UKAS (the Accreditation Body of Great Britain) and RVA (the Dutch Authority) has carried out the whole process of recognition at European level, allowing EA to make itself spokesperson for the recognition of international agreements at ILAC level which will lead to full equivalence between all countries of certificates issued under accreditation.


Reference materials producers operate in a growing number of sectors, from manufacturing to food safety, from health protection to environmental protection. Can you give us examples?

Of the 5 accredited Italian producers, historically the largest number operates in the field of gas, but also of alcoholic solutions (used in the wine sector, for example). Then we have the solid soil matrices used to assess soil contamination in terms of metals present. New frontiers and leading sectors in the future will undoubtedly be the food, but also the new materials used in superconductivity as well as in street lighting.

In fact, scientific research and industrial development are increasingly based on the use of reference materials, because they guarantee metrological traceability, method validation and quality control.