How much time does the space between two heavy black lines (or five squares) represent?

How much time does the space between two heavy black lines (or five squares) represent?

• A. 0.1 seconds
• B. 0.2 seconds
• C. 0.4 seconds
• D. 0.08 seconds

Answer: (B)

The space between two heavy black lines on an EKG strip, which corresponds to five small squares, represents a duration of 0.2 seconds. This is based on the standard calibration of EKG paper, where each small square measures 0.04 seconds. Therefore, when you multiply the duration of one small square (0.04 seconds) by the five squares found between the heavy lines, you arrive at 0.2 seconds. This understanding is crucial for interpreting EKG results accurately, as timing is essential for diagnosing various cardiac conditions. Recognizing the time intervals represented on an EKG allows healthcare professionals to assess heart rate, rhythm, and overall cardiac function effectively.