English Science Science (general) Calibration

Calibration frequency
The question isn’t whether to calibrate — we can see that’s a given. The question is when to calibrate. There is no “one size fits all” answer. Consider these calibration frequencies:


Annually. If you do a mix of critical and non-critical measurements, annual calibration tends to strike the right balance between prudence and cost.
Biannually. If you seldom do critical measurements and don’t expose your meter to an event, calibration at long frequencies can be cost-effective.
Never. If your work requires just gross voltage checks (e.g., “Yep, that’s 480V”), calibration seems like "overkill". But what if your instrument is exposed to an event? Calibration allows you to use the instrument with confidence.

Any help much appreciated, thanks.