1-5 mA

Discernible

5-12 mA

Painful, the sudden contraction of for example an arm muscle, can often throw us off the contact, however this in itself may still be dangerous if it causes us to lose balance from say a set of steps.

13-15 mA

Threshold of involuntary muscle contraction ('let-go' value) after which it is physically impossible to release grasp. [All the muscles in the hand will contract but because the muscles which close the hand are stronger than those which open it, the 'grip' will be sustained]

20-50 mA

Severe pain and loss of consciousness, although heart and lungs may continue to function unless shock starts during critical 'T'-Phase of heart cycle.

50-75 mA

Tetany (paralysis) with no pulse nor respiration; when flow of blood to brain ceases (usually within 3 minutes) damage is irreparable.

100-150 mA

Ventricular fibrillation (disturbance to the coordinated action of the main blood pumping chambers), destroying the heart's natural rhythm with almost instantaneous death.

1500+ mA

Contraction of heart muscle but not necessarily fibrillation, respiratory system may or may not be paralysed.