ABSTRACT

The standard operating procedure describes procedures to be followed for determining whether or not mass standards are within the tolerances specified for a particular class of weights. The tolerance testing method is applicable to all mass tolerance testing. A modified substitution procedure is used to compare the mass to be tested with a calibrated reference mass standard. The reference standard is placed on a balance, a single-pan, an equal-arm, or a full-electronic balance may be used, to obtain a convenient reference point and a sensitivity test is conducted. The error, departure from nominal value, of the weight tested is determined by comparing the balance reading for it to the balance reading for the reference standard. A weight is considered to be within tolerance when its error does not exceed the tolerance established for the particular class of weight.