Mike, It is my understanding that it is purely the responsibility of the owner of the measuring instrument to decide on the calibration period. The calibration laboratory has a financial interest in 'encouraging' its customers to calibrate frequently, but only the customer knows the use to which the instrument is put, and the calibration history. For instance, it may be quite reasonable for gauge blocks, used infrequently to internally calibrate vernier calipers, to be sent out to an external lab for calibration once every five years. On the other hand, the appropriate calibration interval for a vernier caliper in constant use on the production line may be one month or less, especially if the result of out-of-calibration measurements could be a product recall.
Ultimately the manufacturer must take responsibility. If you think about it, I don't think that a calibration laboratory's insurers would want them to take responsibility for specifying calibration periods which may be inappropriate for the actual use to which the measuring device is put. Jon Griver http://www.601help.com The Medical Device Designers' Guide to IEC 60601-1 Subject: Re: Calibration of test equipment From: rehel...@mmm.com List-Post: emc-pstc@listserv.ieee.org Date: Mon, March 20, 2006 4:06 am To: emc-p...@ieee.org Mike, I have searched for this answer before. I have not found anything anywhere that requires a specific time period between calibration. Just manufacturers recommendations or whatever is agreed between you and your calibration lab. The dangers of extending it beyond a year has been documented previously. Bob Heller 3M EMC Laboratory, 76-1-01 St. Paul, MN 55107-1208 Tel: 651- 778-6336 Fax: 651-778-6252 ========================= It's my understanding that the MRA's require that test instruments used for compliance to European Norms be calibrated by an accredited lab --- in the US, NVLAP, A2LA, and (another?). As a manfacturer, we recommend our products be calibrated yearly. ISO 17025 includes clause 5.10.4.4, which states: "The calibration certificate (or calibration lable) shall not contain any recommendation on the calibration interval except where this has been agreed with the customer. This requirement may be superseded by legal regulations." ISO 17025 is, of course, the basis of accreditation to NVLAP or A2LA and others... My question to the group is: Is there some requirement under the MRA's or European Norms that states equipment must be calibrated periodically, and is "periodically" defined?? It seems to me allowing the customer to decide on when calibration is due (per ISO) can lead to no requirement for calibrations at all, which in turn, puts the whole accreditation issue in question….. I find this hard to believe, but I haven't identified a paragraph makes it clear…. Best Regards, Michael Hopkins Manager, Customer Technical Center Process Instruments Division Thermo Electron Corporation One Lowell Research Center Lowell, MA 01852 Tel: +1 978 275 0800 ext. 334 Mobile: +1 603 765 3736 michael.hopk...@thermo.com www.thermo.com/esd - 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 emc-p...@ieee.org 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 emcp...@ptcnh.net Mike Cantwell mcantw...@ieee.org For policy questions, send mail to: Jim Bacher: j.bac...@ieee.org David Heald: emc-p...@daveheald.com All emc-pstc postings are archived and searchable on the web at: http://www.ieeecommunities.org/emc-pstc
