CDC Clinical Reference Laboratory (CDC CRL)

(A2LA Cert. No. 6909.01) 02/26/2025 Page 2 of 2 2 Calibration and Measurement Capability Uncertainty (CMC) is the smallest uncertainty of measurement that a laboratory can achieve within its scope of accreditation when performing more or less routine calibrations of nearly ideal measurement standards or nearly ideal measuring equipment. CMCs represent expanded uncertainties expressed at approximately the 95 % level of confidence, usually using a coverage factor of k = 2. The actual measurement uncertainty of a specific calibration performed by the laboratory may be greater than the CMC due to the behavior of the customer’s device and to influences from the circumstances of the specific calibration. 3 In the statement of CMC, percentages represent the percent of reading unless otherwise noted. 4 This scope meets A2LA’s P112 Flexible Scope Policy. 5 The type of instrument or material being calibra ted is defined by the parameter. This indicates the laboratory is capable of calibrating instruments that measure or generate the values in the ranges indicated for the listed measurement parameter.