This document stipulates CNAS’s requirements for testing laboratories (including medical laboratories), calibration laboratories (including medical reference measurement laboratories), inspection institutions, reference material/standard sample producers, biological sample banks and proficiency testing providers (hereinafter collectively referred to as Conformity assessment bodies) involve metrological traceability requirements for measurement results when implementing accreditation activities. This document applies to the metrological traceability of testing (including medical testing) and calibration (including medical reference measurements) activities, and also applies to the qualification of testing institutions, reference material/reference sample producers, biological sample banks and proficiency testing providers involving measurements. Assessment activities. The internal calibration implemented by the testing laboratory should meet the provisions of CNAS-CL01-G004 "Internal Calibration Requirements".