Laboratory Equipment Operation & Maintenance Flashcards
7 cards from real CLT practice questions. Tap to flip, then mark Knew It or Still Learning — missed cards come back until you master them.
Read the first 7 Laboratory Equipment Operation & Maintenance flashcards as text
When performing a Coulter principle cell counter QC check, which parameter most directly reflects RBC volume distribution?
Answer: RDW
RDW (Red Cell Distribution Width) directly measures the variability in RBC volume, making it the key parameter for assessing RBC volume distribution on Coulter principle analyzers.
A centrifuge rotor shows visible pitting after routine cleaning. The technologist should:
Answer: Remove it from service and notify the supervisor immediately
Pitting in a centrifuge rotor indicates metal fatigue and potential for catastrophic failure; the rotor must be removed from service immediately as a safety measure.
Which component of a spectrophotometer is responsible for isolating a specific wavelength of light?
Answer: Monochromator
The monochromator (using a prism, diffraction grating, or filter) isolates the desired wavelength of light from a broad-spectrum source for accurate absorbance measurement.
A biosafety cabinet (BSC) Class II Type A2 is PRIMARILY designed to protect:
Answer: Personnel, product, and environment
Class II Type A2 BSCs provide triple protection — personnel (via inward airflow), product (via HEPA-filtered downflow), and environment (via HEPA-filtered exhaust).
During autoclave validation, biological indicators (BIs) containing Geobacillus stearothermophilus spores are used because these spores:
Answer: Represent the most heat-resistant organisms
G. stearothermophilus spores are the gold standard BI for steam sterilization because they are among the most heat-resistant organisms, ensuring sterilization efficacy when they are killed.
A laboratory thermometer used to monitor a -80°C freezer reads -75°C during a routine check. The FIRST corrective action is to:
Answer: Verify the reading with a calibrated NIST-traceable thermometer
Before taking action on a temperature discrepancy, the reading must be verified with a calibrated reference thermometer to determine if the issue is with the monitoring thermometer or the freezer itself.
When using an automated coagulation analyzer, a prolonged clot detection time on all channels simultaneously most likely indicates:
Answer: Instrument optical or mechanical system failure
When all channels are affected simultaneously, a systemic instrument problem — such as optical sensor failure or mechanical timing error — is the most probable cause rather than individual reagent or sample issues.