CCE CCE - Certified Clinical Engineer Medical Device Electrical Safety and Testing Questions and Answers 2

Question 1

In IEC 60601-1 terminology, a 'Type CF' applied part provides:

Accepted Answer

The highest level of protection, suitable for direct cardiac application with the lowest allowable leakage current limits

Answer

Type CF (cardiac floating) applied parts have the strictest leakage current limits and are specifically designed for direct or indirect cardiac applications.

Question 2

Macroshock refers to electrical current that:

Accepted Answer

Passes through the surface of the body at levels detectable by the patient, potentially causing ventricular fibrillation at currents above about 100 mA

Answer

Macroshock is the effect of current flowing through the intact body surface; ventricular fibrillation can occur at approximately 100 mA when current traverses the chest.

Question 3

Microshock is particularly dangerous for patients because:

Accepted Answer

Current is applied directly to or near the heart via an intracardiac catheter, so as little as 10 µA can induce ventricular fibrillation

Answer

When current bypasses skin resistance and reaches the myocardium directly, only about 10 µA is needed to trigger ventricular fibrillation, compared to 100 mA for macroshock.

Question 4

Which test instrument is specifically designed to measure leakage currents and chassis resistance during biomedical electrical safety testing?

Accepted Answer

An electrical safety analyzer (e.g., Fluke ESA620 or equivalent)

Answer

Dedicated electrical safety analyzers are calibrated to measure chassis leakage, patient leakage, and ground resistance according to NFPA 99 and IEC 60601-1 methods.

Question 5

What is the maximum patient leakage current allowed under normal conditions for a Type BF applied part per IEC 60601-1?

Accepted Answer

100 microamperes

Answer

IEC 60601-1 limits normal condition patient leakage current for Type BF applied parts to 100 µA, balancing safety with clinical utility.

CCE - Certified Clinical Engineer Practice Test

CCE - Certified Clinical Engineer Practice Test

CCE CCE - Certified Clinical Engineer Medical Device Electrical Safety and Testing Questions and Answers 2