MLPAO Laboratory Equipment and Quality Questions and Answers 2

Question 1

What is the function of a micropipette calibration check using gravimetric analysis?

Accepted Answer

To verify the pipette delivers the correct volume by weighing dispensed water

Answer

Gravimetric calibration checks a micropipette's accuracy by weighing aliquots of distilled water dispensed at the set volume, using the known density of water (1.00 g/mL at 20°C) to calculate the delivered volume.

Question 2

What is the purpose of the discriminator setting on a hematology analyzer for cell counting?

Accepted Answer

To define voltage thresholds that distinguish cell populations by size or electrical impedance

Answer

Discriminators are electronic threshold settings on hematology analyzers that define boundaries between cell populations (e.g., between RBCs and platelets, or between WBC populations) based on electrical impedance or light scatter characteristics.

Question 3

Which of the following calibration materials is appropriate for calibrating a clinical chemistry analyzer?

Accepted Answer

Commercially prepared calibrators with established analyte concentrations traceable to reference methods

Answer

Calibrators are commercially prepared materials with certified analyte concentrations that are traceable to primary reference standards. They are used to set the analyzer's response curve, not QC materials.

Question 4

What is the purpose of preventive maintenance on laboratory analyzers?

Accepted Answer

To ensure consistent analyzer performance, extend instrument life, and prevent unexpected failures

Answer

Preventive maintenance (PM) involves scheduled cleaning, inspection, and replacement of components to maintain consistent analyzer performance, prevent unexpected breakdowns, and extend instrument lifespan.

Question 5

An autoclave is used for sterilization in medical laboratories. What is the minimum recommended temperature, pressure, and time for a standard gravity cycle sterilization?

Accepted Answer

121°C, 15 psi, 15-20 minutes

Answer

Standard gravity displacement autoclave sterilization requires 121°C (250°F) at 15 psi steam pressure for a minimum of 15-20 minutes to achieve sterility (destruction of all microorganisms including resistant spores).

MLPAO - Medical Laboratory Professionals Association of Ontario Practice Test

MLPAO - Medical Laboratory Professionals Association of Ontario Practice Test

MLPAO Laboratory Equipment and Quality Questions and Answers 2