ABSTRACT
Even though he or she is given a part drawing with complete and unambiguous specifications, the metrologist must contend with problems of uncertainty introduced by the equipment and the inspection procedures. The metrologist or inspector must properly align the part during setup; make a complete set of measurements; verify and allow for inaccuracies in equipment, environment, and measuring procedures; and ensure the repeatability of inspection results by recording setup and measurements fully on the inspection report. As a rule-ofthumb, all this must be accomplished so that measurement uncertainty generally will not consume more than 10% to 20% of the part tolerance.
