Florida State Paramedic Practice Exam

How long is a small block on EKG paper?

1. 0.02 seconds

2. 0.04 seconds

3. 0.06 seconds

4. 0.08 seconds

The correct answer is: 0.04 seconds

A small block on EKG paper represents a duration of 0.04 seconds. This is based on the standard EKG paper speed, which is usually set at 25 millimeters per second. Each small square on the paper has a width of 1 millimeter, and since the paper moves at this rate, each small block corresponds to a 0.04-second interval (1 mm divided by 25 mm per second). This measurement is critical for interpreting EKG readings, as it allows healthcare providers to assess the timing of the cardiac cycle, including intervals such as the PR interval, QRS duration, and QT interval. Accurately understanding the duration of these intervals can signal various cardiac conditions. Thus, recognizing that each small block equals 0.04 seconds helps in measurements and interpreting the heart's electrical activity effectively.