CBET Preventive Maintenance and Calibration 5

Question 1

When using a electrical safety analyzer to perform a leakage current test on a Class I medical device, what is the maximum allowable chassis leakage current under normal conditions per NFPA 99?

Accepted Answer

100 µA

Answer

NFPA 99 and AAMI ES60601-1 limit chassis (enclosure) leakage current for Class I devices to 100 µA under normal conditions.

Question 2

A biomedical technician is calibrating a non-invasive blood pressure (NIBP) module. Which instrument is required to verify cuff pressure accuracy?

Accepted Answer

A certified digital manometer or pressure calibrator

Answer

A calibrated digital manometer or pressure calibrator directly measures the pneumatic pressure applied to the cuff, providing a traceable reference for NIBP calibration.

Question 3

Which PM task is unique to laser surgical equipment compared to conventional electrosurgical units?

Accepted Answer

Verifying beam alignment, output power, and protective eyewear integrity

Answer

Laser PM includes optical alignment verification, measured output power against rated specifications, and inspection of safety interlocks and wavelength-appropriate eyewear.

Question 4

During PM on a physiological monitor, the technician observes that the ECG trace has a 60 Hz artifact that persists after replacing lead wires. The next troubleshooting step is:

Accepted Answer

Verify the device chassis ground continuity and check the common mode rejection ratio (CMRR)

Answer

Persistent 60 Hz artifact after lead replacement typically indicates a grounding deficiency or degraded CMRR in the amplifier, both assessed during PM.

Question 5

A PM procedure requires lubricating the drive mechanism of an OR table. Which lubricant is contraindicated in this environment?

Accepted Answer

Petroleum-based grease where O-rings or oxygen lines are nearby

Answer

Petroleum-based lubricants can degrade rubber O-rings and create fire or explosion hazards in oxygen-enriched surgical environments.

CBET - Certified Biomedical Equipment Technician Practice Test

CBET - Certified Biomedical Equipment Technician Practice Test

CBET Preventive Maintenance and Calibration 5