One little misconception someone cleared up for me a few years ago, is the difference between 'calibration' and 'verification.'
- Calibration-performed by a certified accredited vendor
- Typically this is quarterly or annually, depending on risk or manufacturers recommendations
- Verification- Can be performed in house by a trained employee
- Typically performed with ice bath, boiling point, by using a verification thermometer (or mixture of the 3)
- You can usually find the recommended verification procedures and frequency under 'maintenance' sections of the thermometer's manual, however depending on your risk you might want to do this weekly, daily, per shift, etc.
EDIT: I've almost always ever just replaced the thermometers at the 1 year mark as they come calibrated. The price to send them out to a certified accredited vendor and then deal with that hassle of making sure they are up on their certifications, that they will get them back to you in a timely manner, and that they will possibly just charge you to tell you that you need a new thermometer, made it not ever seem worth getting them calibrated in my experience.
In practice, these terminologies along with Validaton often become a semantic, metrological, nightmare for the ordinary human being.
With paracetamol at the ready, welcome to digest the first 2 attachments below followed by the somewhat less head-banging 3rd file.
IIRC, "Calibration" of equipment is often referred to in haccp texts as a "Verifcation" activity for the haccp team.
Perhaps someone should (cautiously) sponsor the terminologies internal/external Calibration.
in-house Calibration - UKAS-LAB_14_Edition5July2015.pdf 308.81KB
calibration, Verification, etc.pdf 2.18MB