Why do calibration standards need to be calibrated every three years?

Simply put to insure quality There are many kinds of calibration standards out there. We at, Exaxol, make ICP, AA, Ion Chromatography, EPA, pH, and Conductivity standards among other things. They all have different shelf lives due to there matrix or stabilizers.

Many require high purity acids to dissolve in solution and over time CO2 from the air will make carbonic acid in your standardized solution. This will affect pH dependent solutions and add impurities Tolerances are a big deal in many industries and even mechanical and digital measuring devices such as scales and electrodes need to be checked annually to maintain accuracy in your work I added a link to a more lengthy pH discussion if you were looking for more than a short answer response! Www.exaxol.com.

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