Maintenance Protocols Drive Testing Accuracy
By: Chris Wetzel, MLS (ASCP)
Laboratory Specialist
Posted: August 18, 2025
Testing quality and equipment accuracy go hand in hand in ACHC-accredited laboratories. Maintenance protocols are essential to reliable testing results. ACHC Laboratory Standards and best practice dictate what to do and how to do it to maintain the performance of equipment, instruments, and test systems.
The laboratory should review all operators’ manuals to determine if the manufacturer recommends any maintenance. If so, this should be incorporated into the overall maintenance program. If the manufacturer does not include a recommended maintenance procedure, the laboratory must define its own process and establish a schedule based on the equipment’s workload and operational requirements.
This aligns with ACHC Standard 06.04.02 Modified System Maintenance Checks which states:
For equipment, instruments, or test systems developed in-house, commercially available, and modified by the laboratory, or for which maintenance and function check protocols are not provided by the manufacturer, the laboratory must:
1. Establish a maintenance protocol that ensures equipment, instrument, and test system performance that is necessary for accurate and reliable test results and reporting.
2. Perform and document the maintenance activities.
Establishing Specific Maintenance Protocols
Examples of equipment to which this standard may apply and considerations for maintenance appear in the table below.
Note: This is not an exhaustive list.
| Centrifuges | Centrifuges should be cleaned regularly and when a spill occurs. The RPM should be assessed at least annually. Check the timer on the centrifuge as well. If you have a refrigerated centrifuge, the temperature should be verified. Centrifuge records should include the RPM readings and list the manufacturer’s tolerance limits to verify whether compliance is achieved. |
| Microscopes | Microscopes should be cleaned as needed with preventive maintenance performed at least annually. |
| Pipettes | Most manufacturers recommend simple cleaning and minor maintenance. Calibration should take place at least annually. For high-volume use and blood bank pipettes, the frequency should be increased to semiannually. Adjustable pipettes should be calibrated at multiple volumes to ensure accuracy. |
| Thermometers | Thermometers should be NIST-certified or traceable to a NIST-certified thermometer. Once the certification expires, the laboratory should verify the accuracy of the thermometer annually using a thermometer with a current calibration and within defined tolerance limits. For equipment with a digital temperature display used for daily monitoring, the laboratory should verify that the readout is accurate. This should be done at instrument placement and follow any further manufacturer recommendations. |
| Timers | Timers typically come with a calibration report that includes an expiration date (sometimes accompanied by a sticker on the timer). Once this calibration expires, the laboratory should verify the accuracy of the timers annually. Some laboratories purchase all new timers each year, while others purchase one new timer and compare the “old” timers to this new one. The laboratory should define its method to include tolerance limits. |
Overall Best Practice
The laboratory must define maintenance procedures for all equipment involved in the testing process and establish the frequency at which these procedures should be performed. The frequency should not be less than the manufacturer’s recommendations. Procedures should include tolerance limits where applicable. Records of calibration, certification, verification, and other relevant documents should be retained for at least two years. Initial verification records should be kept for the life of the instrument plus two years.
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