Ian, An accredited laboratory will be operating to ISO 17025 and will provide a statement uncertainty of measurement for any item that they calibrate. This is essential to have if you want to be able to make a statement of uncertainty of measurement for any tests that you perform with that equipment. Also, the calibration methods for an accredited calibration will generally have a shorter line of traceability to national standards. In many countries calibration that is not accredited is simply not recognised.
I think the UK is unusual in there being a large segment of calibration providers who operate to standards, and can prove a line of traceability, but are not operating strictly to ISO 17025; more likely operating to ISO 9001 + ISO 10012. UKAS calibration is often more costly than a non-accredited calibration because it is impossible, or at least very difficult, to calculate the measurement uncertainty for automatic calibrators such as are used routinely for instruments such as oscilloscopes or multimeters. Best regards Neil R. Barker CEng MIET HonFSEE MIEEE Manager Quality Engineering e2v technologies (uk) ltd 106 Waterhouse Lane Chelmsford Essex CM1 2QU UK Tel: (+44) 1245 453616 Fax: (+44) 1245 453571 Mob: (+44) 7801 723735 P Please consider the environment before printing this email. From: Gordon,Ian [mailto:[email protected]] Sent: 31 October 2007 10:15 To: 'IEEE EMC & SAFETY PSTC' Subject: UKAS v standard calibration All Can anyone explain the merits (if any) of obtaining a UKAS (or other accreditation body outside the UK) calibration rather than a calibration based upon traceable standards for a piece of test equipment, and what is the difference? Ian Gordon Sent by E2V TECHNOLOGIES PLC or a member of the E2V group of companies. A company registered in England and Wales. Company number: 04439718. Registered address: 106 Waterhouse Lane, Chelmsford, Essex, CM1 2QU, UK. - This message is from the IEEE Product Safety Engineering Society emc-pstc discussion list. Website: http://www.ieee-pses.org/ To post a message to the list, send your e-mail to [email protected] Instructions: http://listserv.ieee.org/request/user-guide.html List rules: http://www.ieee-pses.org/listrules.html For help, send mail to the list administrators: Scott Douglas [email protected] Mike Cantwell [email protected] For policy questions, send mail to: Jim Bacher: [email protected] David Heald: [email protected] All emc-pstc postings are archived and searchable on the web at: http://www.ieeecommunities.org/emc-pstc ______________________________________________________________________ This email has been scanned by the MessageLabs Email Security System. For more information please visit http://www.messagelabs.com/email ______________________________________________________________________
