CMLA Laboratory Equipment Operation & Maintenance 3

Question 1

What does a Levy-Jennings chart primarily monitor in a clinical laboratory?

Accepted Answer

Quality control results over time to detect trends and shifts

Answer

Levy-Jennings charts plot QC values over time, allowing laboratory staff to detect shifts, trends, and random errors visually.

Question 2

When should a biological safety cabinet (BSC) blower be turned on before beginning work?

Accepted Answer

At least 5 minutes before use to purge and stabilize airflow

Answer

Running the BSC blower for at least 5 minutes before use ensures stable, uncontaminated airflow that protects both the worker and specimen.

Question 3

An automated hematology analyzer produces a flagged result for white blood cell count. What is the appropriate next step?

Accepted Answer

Prepare and review a peripheral blood smear for manual differential

Answer

Flagged hematology results require peripheral smear review to confirm or further characterize abnormalities before reporting.

Question 4

Which type of water is recommended for most laboratory reagent preparation?

Accepted Answer

Deionized or distilled Type I or Type II reagent-grade water

Answer

Reagent-grade (Type I or II) water meets purity standards for conductivity and contaminants necessary for accurate laboratory testing.

Question 5

What action should be taken if a pH meter reads outside the expected range when checked with a standard buffer?

Accepted Answer

Recalibrate the meter using certified buffers at known pH values

Answer

Recalibration with certified buffers corrects the electrode response curve so subsequent measurements are accurate.

(CMLA) Certified Medical Laboratory Assistant Practice Test