Code of Federal Regulations Title 42. Public Health § 42.493.1255 Standard:  Calibration and calibration verification procedures

(i) Using calibration materials appropriate for the test system and, if possible, traceable to a reference method or reference material of known value;  and

(ii) Including the number, type, and concentration of calibration materials, as well as acceptable limits for and the frequency of calibration;  and

(i) Including the number, type, and concentration of the materials, as well as acceptable limits for calibration verification;  and

(ii) Including at least a minimal (or zero) value, a mid-point value, and a maximum value near the upper limit of the range to verify the laboratory's reportable range of test results for the test system;  and

(i) A complete change of reagents for a procedure is introduced, unless the laboratory can demonstrate that changing reagent lot numbers does not affect the range used to report patient test results, and control values are not adversely affected by reagent lot number changes.

(ii) There is major preventive maintenance or replacement of critical parts that may influence test performance.

(iii) Control materials reflect an unusual trend or shift, or are outside of the laboratory's acceptable limits, and other means of assessing and correcting unacceptable control values fail to identify and correct the problem.

(iv) The laboratory's established schedule for verifying the reportable range for patient test results requires more frequent calibration verification.