Electrical Injuries: What Happens to the Body
It doesn’t take much current to kill. The amount flowing through a 15-amp household circuit is many times what can stop a heart. Knowing what electricity does to the body explains why the rules are so strict, and why every shock deserves a trip to a doctor.
- All workers
- Electricians
How current affects you
Approximate effects of 60 Hz AC current flowing through the body for about one second:
| Current | Likely effect |
|---|---|
| About 1 milliamp (mA) | Barely felt |
| About 5 mA | Slight shock; GFCIs are designed to trip around here |
| 6 to 30 mA | Painful shock; muscles may lock so you can’t let go |
| 50 to 150 mA | Extreme pain, breathing can stop, severe muscle contractions; death possible |
| 1,000 to 4,300 mA | Heart rhythm disrupted (ventricular fibrillation); nerve damage; death likely |
| 10,000 mA and up | Heart stops; severe burns; death probable |
Wet skin, sweat, cuts and standing in water lower your body’s resistance, so more current flows at the same voltage.
Types of injuries
- Electrocution: death from electric shock, usually from the heart going into fibrillation or breathing stopping.
- Internal burns: current heats tissue along its path. There may be small entry and exit wounds with serious damage to muscle, nerves and organs underneath.
- Arc flash burns: intense heat from an arc burns skin and ignites clothing. See Arc Flash.
- Falls: a shock can throw you off a ladder or scaffold, or make you lose your grip.
- Delayed effects: heart rhythm problems, nerve damage, muscle breakdown that harms the kidneys, cataracts, memory problems and PTSD can show up hours to months later.
If someone is shocked
- Don’t touch them if they may still be in contact with the source.
- Shut off the power at the breaker or disconnect, if you can do it safely.
- Call 911.
- Once it’s safe, check breathing. Start CPR and use an AED if they’re not breathing normally. See CPR & AED.
- Cover burns loosely with clean, dry dressings. See Burn First Aid.
- Watch for signs of shock and keep them warm and still.
For high-voltage contacts or downed lines, stay away and wait for the utility. See Downed Power Lines.
Get checked after every shock, even if you feel fine. A doctor may want an ECG to check your heart rhythm. Report it to your supervisor too; it’s a sign something is wrong with the equipment. See Reporting Incidents.
Standards & references
Last updated: