Normal ECG

Should have P ,Q, R,S and T waves

P wave should be followed by QRS complex and QRS complex followed by T wave

P - R interval should be Normal and constant: between 3 to 5 small boxes(0.12–0.20 seconds)

QRS complex should be narrow ,i.e. between 1-3 small boxes(<0.12 seconds)

R-R interval should be regular

Heart rate should be Between 60 to 100/min

Should have pulse