ECG ECG Equipment and Maintenance

Question 1

What is the standard paper speed used for ECG recordings in the United States?

Accepted Answer

25 mm/sec

Answer

The standard ECG paper speed in the US is 25 mm/sec, which allows accurate measurement of intervals and waveforms.

Question 2

What voltage does each large square on ECG paper represent at standard calibration?

Accepted Answer

1 mV

Answer

At standard calibration (10 mm/mV), each large square (10 small squares tall) represents 1 mV of voltage.

Question 3

How often should ECG electrodes be replaced to ensure optimal signal quality?

Accepted Answer

Per patient use (single-use)

Answer

Disposable ECG electrodes are single-use and should be replaced for each patient to prevent cross-contamination and ensure good conductivity.

Question 4

What is the function of the galvanometer in an ECG machine?

Accepted Answer

Measures and records voltage differences

Answer

The galvanometer detects and records small voltage differences between electrodes, converting electrical activity into a visual tracing.

Question 5

Which filter setting on an ECG machine is used to reduce muscle artifact?

Accepted Answer

Low-pass filter

Answer

A low-pass filter cuts high-frequency signals such as muscle (EMG) artifact, producing a cleaner ECG tracing.

ECG (Electrocardiogram) Practice Test