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How to Properly Store and Handle Test Weights

Test weights are used to perform calibrations. It is very important to maintain their accuracy, and to do so there needs to be proper handling and storage of the test weights. If their accuracy is compromised, then calibrations will be off and product will be out of spec.


Class 1-7 test weights are held to the American Society for Testing and Materials (ASTM) standards and are most used in the laboratory.

These test weights should be kept in their original packaging. This with help keep dust and residue off the weights and keep them together. Store the weights near the balance to ensure they are controlled within the same temperature during use. An ideal temperature is 68 degrees Fahrenheit ± 2

When handling the test weights, be sure to use non-magnetic and non-abrasive tweezers. When possible, wear approved gloves. You should never use your bare hands to handle the test weights. The oils from your skin can affect the accuracy.


Class F test weights are held to NIST standards and are most often used in an industrial setting to calibrate larger scales.

These test weights aren’t required to be in as specific conditions as Class 1-7 test weights due to the tolerances involved. Just store these test weights in a clean dry environment and away from major contaminants.


Keeping your test weights under these conditions will save money because failure to do so results in re-calibration and decontamination of the test weights.

If you are in need of a calibration, we would be happy to assist you.




Calibration Weights

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