John Wilson
There is a lot of confusion about “accredited calibration”, why it is required and what it is really about. Firstly, it is a voluntary exercise for most companies as it gives them peace of mind but in certain cases, where it is specified by a regulator, it is a mandatory requirement. The ISO/IEC 9001 standard simply requires that test equipment used in a facility must be calibrated. It does not specify by whom or to what uncertainty (see EngineerIT August 2015, page 12). If the test equipment is calibrated by a non-accredited laboratory, the onus lies with the company requesting the calibration (customer) to be sure that the laboratory doing the calibration is competent to do so. This would normally mean that the customer would need to visit the laboratory and effectively do a technical assessment to see if they are able to do the work required, to an acceptable standard. This is a costly exercise for both the customer and laboratory and requires that the customer has technically competent staff to do the assessment.
The accreditation process moves the assessment function to an accreditation body (AB) to do the assessment on the customer’s behalf. In fact, it is the laboratory that voluntarily requests to be accredited so that their customers do not need to come and visit them and thus save both parties time and money. John Wilson of Accreditation & Metrology Services answers the following questions.
Contact jgpwilson@xsinet.co.za
What ISO standard is applicable to laboratory accreditation?
The correct standard used for calibration and testing laboratory accreditation is ISO/IEC 17025 “General requirements for the competence of testing and calibration laboratories”. There is a similar standard known as ISO 15189 for medical laboratories. These standards are very similar as they are based on evaluating the competence of a laboratory to conduct work according to an assessed schedule and appropriate uncertainties. The standard comprises of basically two parts. They are the quality management section (very similar to the requirements of ISO 9001) and the technical section related to competence of the technical work to be carried out.
What is the National Accreditation body?
In South Africa, the South African National Accreditation Service (SANAS) (www.sanas.co.za), is the organisation, empowered by an act of parliament, to be the national accreditation body. In turn, SANAS is a signatory to the International Laboratory Accreditation Co-Operation (ILAC) mutual recognition arrangement. This means that SANAS is also assessed by the international body to see that they are operating correctly. The ILAC web site (http://ilac.org/ilac-mra-and-signatories/) also lists the ABs around the world who are similarly assessed. This leads to the ILAC motto of “measure once, accepted by all” which means that once a product has been tested in any laboratory accredited by an AB that is a signatory to the ILAC MRA, those results are to be accepted by all and local testing does not have to happen again.
What is the accreditation process?
The laboratory wishing to be accredited applies to SANAS to accredit them against a schedule that the laboratory draws up. This schedule covers the range of measurements they wish to conduct in their laboratory and they need to specify the uncertainty (or accuracy) they believe that they can achieve. SANAS will request a copy of the laboratory quality manual and do a pre-assessment of the laboratory. If all appears to be in order, then SANAS will send an assessment team comprising of a lead assessor and appropriate technical assessors to evaluate the competence of the laboratory to perform the work they have applied to be assessed for. This assessment can take a few days depending on the range of the schedule as everything needs to be checked in detail by the assessors. The laboratory has to prove by demonstration to the assessors that they can do the required work to the claimed uncertainty. Similarly it is not only the head of laboratory that is assessed, all the laboratory personnel that requested to be the technical signatories need to be assessed for the range of work that they will be conducting. After the initial assessment, there are periodic re-assessments by SANAS of the laboratory as well as the right to visit the laboratory at any time to do a quick assessment and to submit the laboratory to “blind audits” all of which are to see that the laboratory continues to maintain the quality of work they are assessed for.
Why use an accredited laboratory?
By using an accredited laboratory, the customer reduces the risk of using or producing a product that does not conform to the required specifications or industry standards. It also removes the need to have a product re-tested in another laboratory overseas if your product is to be exported and finally it provides confidence to your clients that they know your product has been tested by an independent, competent, testing or calibration laboratory. This accredited service will cost a little more than a test or calibration performed by a non-accredited facility. However, a SANAS laboratory certificate enjoys a legal status as envisaged by Section 25 of Act 19 of 2006. So is the reduced cost worth the risk? Only you or your customer can make that decision.
