About Test / Calibration Weights
Accuracy is vital as weights are used to calibrate scales and other weighing equipment, an inaccurate weight, in turn, will have a knock-on effect and will produce erroneous scale calibration. A calibrated set of weights allows the balance scale error to be assessed and corrected to the highest accuracy.
The periodicity of calibration is dependent on weight use and the accuracy class of the weights but annual calibration is generally advised.
The International Organisation of Legal Metrology (OIML) is an intergovernmental organisation that provides standards and systems to harmonise legal metrology procedures. From lowest (most accurate) to highest tolerance, the OIML classes are E1, E2, F1, F2, M1, M2, and M3. Most laboratory applications require OIML weights of Class F2 or below.