CHBT Electrical Safety and Biomedical Engineering Principles

Question 1

What is the maximum allowable leakage current for patient-connected medical equipment according to AAMI/IEC standards?

Accepted Answer

100 microamperes

Answer

10 microamperes

Answer

50 microamperes

Answer

500 microamperes

Question 2

Which type of grounding system is specifically required for patient care areas in dialysis units to minimize electrical hazards?

Accepted Answer

Isolated power system

Answer

Standard two-wire grounding

Answer

Equipotential grounding system

Answer

Double-insulated system

Question 3

In the context of hemodialysis equipment, what does 'macroshock' refer to?

Accepted Answer

Current above 1 mA applied to the skin surface

Answer

Current applied directly to the heart via a catheter

Answer

Electrical discharge from a capacitor

Answer

Static electricity buildup on equipment

Question 4

What is the primary purpose of a line isolation monitor (LIM) in a dialysis unit?

Accepted Answer

To detect loss of isolation in an isolated power system

Answer

To measure voltage output of dialysis machines

Answer

To regulate current flow to the blood pump

Answer

To monitor water quality in the dialysate circuit

Question 5

Which class of medical electrical equipment relies solely on basic insulation for patient protection with NO protective earth connection?

Accepted Answer

Class II

Answer

Class I

Answer

Class III

Answer

Type CF

Question 6

What is the recommended frequency for electrical safety testing of patient-connected hemodialysis equipment per AAMI standards?

Accepted Answer

Every 6 months

Answer

Monthly

Answer

Annually

Answer

Every 2 years

Question 7

What is 'microshock' hazard in hemodialysis patients particularly relevant for those with central venous catheters?

Accepted Answer

Currents as low as 10–20 microamperes applied directly to the heart

Answer

Currents of 1–100 mA applied externally to the body

Answer

High-voltage discharges from capacitors

Answer

Ground fault currents exceeding 5 mA