A preventive maintenance plan for a common laboratory analyzer should include which elements?

• A. Schedule calibration, service, parts replacement; record maintenance; run QC before patient results; monitor drift
• B. Only cleaning at end of day
• C. Replacing the entire system yearly
• D. Ignoring QC during maintenance

Answer: (C)

The main idea is that a preventive maintenance plan for a lab analyzer should actively verify and preserve measurement accuracy over time. The best approach combines several interrelated practices: scheduling calibration and regular service, replacing worn parts as needed, keeping thorough records of all maintenance activities, running quality control before reporting patient results, and monitoring drift to catch performance changes early. This combination ensures the instrument remains accurate, reliable, and traceable, which is essential for patient testing and regulatory compliance.

Simply cleaning at the end of the day fails to ensure accuracy or detect drift. Replacing the entire system yearly is not practical or necessary and bypasses routine checks that catch wear and performance issues. Ignoring QC during maintenance defeats the purpose of QC, since QC acts as the ongoing checkpoint that confirms the analyzer is delivering correct results.