The electrocardiogram (ECG, EKG) is standardized for time and voltage.
Standard ECG paper has 1 mm squares in the X and Y direction, with thicker lines demarcating 5 squares.
The X axis of the strip indicates time in seconds or milliseconds.
The Y axis indicates voltage in millivolts.
Axis
|
1 mm square
|
5 mm square
|
X (time)
|
0.04 seconds (40 msec)
|
0.20 seconds (200 msec)
|
Y (voltage)
|
0.1 millivolts
|
0.5 millivolts
|