Per Clinical Laboratories Improvement Amendment (CLIA) regulations 493.1254: Maintenance and Function Checks section b.1.i:  Equipment, instruments, or test systems developed in-house, commercially available and modified by the laboratory, or maintenance and function check protocols not provided by the manufacturer. The laboratory must do the following: Establish a maintenance protocol that ensures equipment, instrument, and test system performance that is necessary for accurate and reliable test results and test-result reporting.