Why Accredit Reference Materials Producers?
The use of certified reference materials (CRM) and/or reference materials (RM) in testing and calibration laboratories is critical for ensuring that any established traceability chain to SI units is unbroken. As a consequence, all method validation and instrument calibration performed in testing/calibration laboratories must provide confidence, integrity and accuracy in the laboratory’s management of traceability to national and international primary measurement units. One of the key factors affecting laboratories' capabilities to produce reliable test data is the availability of reference materials with certified values that can be relied upon by their users.The demand for new reference materials of demonstrated and reliable quality is increasing as a consequence of both the increased precision of measuring equipment and the requirement for more accurate and reliable data in the scientific and technological disciplines. It is therefore not only necessary for Reference Material Producers (RMPs) to supply information about these materials in the form of reports, certificates and statements, but also to demonstrate their competence in certifying reference materials of appropriate quality.
A number of international guides have been prepared through bodies such as ISO/REMCO to increase confidence in reliability of reference materials (refer below to ‘What are the Requirements for Accreditation?’)
An internationally-recognised accreditation program for producers of reference materials is currently available at NATA.
What are the Requirements for Accreditation?
NATA evaluates the reference materials producer, and any subcontracting arrangements it uses, against the following core and normative documents:Core Documents:
- ISO Guide 34 (2009) – Requirements for the Competence of Reference Material Producers;
- ISO/IEC 17025 (2005) – General requirements for the competence of testing and calibration laboratories;
- NATA RMP Field Application Document.
- ISO Guide 31 (2000) Reference materials – Contents of certificates and labels;
- ISO Guide 35 (2006) Reference materials – General and statistical principles for certification.
How Does NATA Accredit Reference Materials Producers?
There are many different ways for producers to certify reference materials. These range from all functions being performed by a single organisation, through to various combinations of organisations conducting separate tasks leading to the production and value assignment (ie. Certification) of a reference -material. NATA considers that the organisation which is responsible for producing a reference material with an assigned value should ensure that all sub-tasks leading to its production have been performed competently, whether such tasks are carried out directly by the producer itself or in combination with various subcontractors.Accordingly, it is the producer (and any subcontracting arrangements it uses) which NATA evaluates for competence in accordance with the standards listed above.
Accreditation of a producer of reference materials is granted in terms of a defined scope of accreditation, which describes the specific categories of reference materials which the producer is judged competent to produce. The scope of accreditation is discussed with each applicant and on an on-going basis with accredited RMPs to broadly represent the categories of reference materials the facilities are producing.
How Does NATA Evaluate the Competence of a Producer?
NATA evaluates a producer's compliance with the ‘Requirements’ using assessment teams comprising technical experts and full-time NATA staff. In this respect it is similar to NATA's laboratory accreditation assessments. NATA is advised by a Reference Material Producers Accreditation Advisory committee in:- the appointment of technical assessors
- the development and review of accreditation requirements and
- providing recommendations for granting and maintaining accreditation
