Accredited PTPs and interlaboratory tests compliant with the standards guarantee correct processes and more reliable results. Worldwide mutual recognition brings benefits to all those involved. We talk about it with Dr. Silvia Tramontin, Director of the Testing Laboratories Department.
What are PTPs and what is their role?
To understand the importance of PTPs, it is necessary to start from the activity of testing laboratories, that need to produce reliable and reproducible results. To verify the correctness of its processes, laboratories periodically undergo interlaboratory comparisons organized by the Proficiency Testing Providers (PTP). The role of PTPs is essential, because it is not enough to have the same sample tested by different laboratories, a well codified and structured process must be followed. At the end of the test, the PTP evaluates the performance of each participating laboratory, assigning a score calculated according to statistical systems.
What are the reference standards that regulate this activity?
Until 2010 the ISO/IEC Guide 43 was applied, which provided indications on how interlaboratory comparisons should be organized. In 2010, ISO/IEC 17043 was published, a globally harmonized standard, under which accreditation bodies can accredit PTPs. This standard introduces rules that all PTPs must respect with regard to the preparation of the sample to be tested and the characteristics that it must have, to the shipping methods, to the determination of its “true” value, valid for all laboratories.
How does Accredia affect the PTP activity?
Accredia verifies that the organization process of proficiency tests followed by the PTPs is correct and compliant with the ISO / IEC 17043 standard. An accredited PTP is able to guarantee the conformity of its work and is therefore more competitive. Furthermore, although not mandatory, PTP accreditation is strongly recommended due to a virtuous circle involving the laboratories themselves. Among the requirements for the accreditation of testing laboratories, in fact, there is the participation in interlaboratory comparisons in compliance with ISO/IEC 17043. If the PTP is not accredited, laboratories must qualify their supplier, taking responsibility for the conformity assessment against ISO/IEC 17043, for example through a specific verification with the ILC organizer, which represents an additional obstacle.
What is the international situation and what changes with the new ILAC MRA international Agreement?
At European level the PTP accreditation schemes in compliance with ISO/IEC 17043 started in 2017. Accredia, following the passing of peer evaluations between Accreditation Bodies, has acquired the status of signatory member of the 2017 EA MLA international mutual recognition Agreement, valid in Europe. Then, in 2019, it also signed the ILAC MRA Agreement, which extends mutual recognition worldwide. Thanks to this Agreement, accreditation issued in Italy has full recognition within all world economies.
What are the benefits of mutual recognition?
Mutual recognition involves first of all reducing barriers on the international market, so if accreditation in a given sector exists only in Italy, foreign participants can request it and obtain the same benefits, as if they were accredited in their country. Thanks to mutual recognition, testing laboratories can select the proficiency testing provider that best meets their needs from a wider range of accredited PTPs. Finally, the public interest in obtaining reliable analyses is even more protected: laboratories participating in interlaboratory comparisons, in fact, submit their analytical process to verification, to guarantee the quality of their results.