US Clinical Laboratory Improvement Amendments (CLIA) Regulations (42 CFR Part 493) 1254: Perform and document maintenance and function checks for unmodified manufacturer systems as the manufacturer defines and at least as often as specified, with function checks within the manufacturer's limits before patient testing; for in-house, modified or unspecified systems, establish and follow a maintenance protocol and a function check protocol (including background or baseline checks) that ensure reliable results

What does 1254 require?

For unmodified manufacturer's equipment, instruments or test systems the laboratory must perform and document maintenance as defined by the manufacturer at least at the specified frequency, and function checks as defined by the manufacturer at least at the specified frequency, with function checks within the manufacturer's established limits before patient testing is conducted. For equipment, instruments or test systems developed in-house, commercially available but modified by the laboratory, or for which the manufacturer provides no maintenance or function check protocol, the laboratory must establish a maintenance protocol that ensures the performance needed for accurate and reliable results and reporting, perform and document that maintenance, define a function check protocol with the same aim, and perform and document the function checks, including background or baseline checks, which must be within the laboratory's established limits before patient testing.