This document specifies acceptance and periodic reverification tests of CMM performance with contacting probing systems and is only applicable to CMMs using: any type of contacting probing system; and spherical or hemispherical stylus tip(s). NOTE CMM probing performance tests are specified by the maximum permissible errors (MPEs), due to the impracticality of isolating the performance of the probing system from that of the CMM, even on a small artefact such as a test sphere.This document applies to CMMs supplied with any of the following: single-stylus probing systems; multi-stylus probing systems with fixed multiple styli attached to a single probe (e.g. “star?? stylus); multiple probing systems such as those with a stylus for each of their probes; systems with articulating probing systems; stylus and probe changing systems; manual (non-driven) and automated CMMs; installations including a scanning probe, capable of being used in a scanning mode. This document is not applicable to non-contacting probing systems, which require different testing procedures.The term ‘combined CMM and multi-stylus probing system size error’ has been shortened to ‘multi-stylus size error’ for convenience. This applies in similar cases.If it is desirable to isolate the probing system performance as far as is practical, the influence of the CMM can be minimized but not eliminated. See AnnexC for more information.