Leaderboard

We change all batteries annually while we are doing the QA on them so it's not likely that a battery will fail during the year. However, things do happen and I agree with exlimely, if you do have to change or replace (say it fell out for some reason) a battery, then a 'calibration' would be prudent. Also, we are not talking high precision here, i.e. wider acceptability range than a pipette would be, i.e. testing is done in ranges of time, not exact seconds. This 'calibration' is just a simple check up to make sure the timer isn't totally out of range. Most of the time, the error is the readout gets 'broken', not the accuracy of the timer.

If your timers are digital I believe they are exempt from calibration due to the nature of digital timing. They work until the batteries run out of charge. The CAP requirement for timers does not apply to digital ones. TRM.31900. How could you calibrate a digital timer (compare it to the Naval clock?)