Scout Skills

First Aid · Resuscitation

AED Basics

An AED reads a cardiac-arrest victim's heart rhythm and, if it finds a shockable one, delivers a shock to reset the heart. It's built for untrained people — turn it on and it talks you through every step. AED plus early CPR is what saves people.

Category
Resuscitation device
What it does
Analyze, shock if shockable
Golden rule
Nobody touches on shock
After a shock
Resume CPR

How to use it

  1. 1Check and call first. Confirm the person is unresponsive and not breathing; have a bystander call 911 and get the AED.
  2. 2Turn the AED on as soon as it arrives and follow the voice prompts — the device leads you.
  3. 3Bare and dry the chest — remove clothing over it and wipe it dry if it's wet.
  4. 4Attach the pads: one on the upper-right chest, one on the lower-left side a few inches below the armpit. If the pads might touch on a small body, put one on the chest center and one on the back between the shoulder blades.
  5. 5Plug the pad cable into the AED if it isn't already connected.
  6. 6Let it analyze — make sure no one is touching the person; say "CLEAR!" loudly.
  7. 7Shock if advised — again make sure no one is touching, say "CLEAR!", and push the shock button.
  8. 8Immediately resume CPR, starting with compressions, after the shock — or right away if it says no shock is advised. Keep following the prompts.

When to use it

  • Sudden cardiac arrest anywhere an AED is mounted — schools, gyms, camps, airports, many public buildings.
  • The device to grab alongside CPR the moment someone collapses and isn't breathing.
  • Knowing where the AED is at a meeting hall, camp, or event — worth checking before you ever need it.

Common mistakes & safety

  • Never touch the person during analysis or a shock. You can be shocked and you can throw off the rhythm reading. "CLEAR!" is a safety check, not a formality.
  • The chest must be bare and dry. Pads don't stick or conduct through clothing, sweat, or water — move the person off wet ground.
  • Use pediatric pads/settings for a child under 8 or under 55 lb if available. If only adult pads are on hand, follow the device and dispatcher — a shock with adult pads beats no shock.
  • Don't place a pad over an implanted device (a hard lump like a pacemaker) or a medication patch — move the pad slightly and remove a patch with a gloved hand first.
  • An AED does not replace CPR. It works with compressions — the moment it's done, hands go back on the chest.
  • You can't shock someone into harm by mistake. The AED only allows a shock if it detects a shockable rhythm — that's why you can trust its prompts.

Going deeper

  • Why the shock helps. In the most common cardiac-arrest rhythm the heart quivers uselessly (fibrillation); the shock briefly stops all electrical activity so the heart's own pacemaker can restart a normal beat. It's a "reset," not a "jump-start."
  • Designed for laypeople. Clear voice prompts, some with diagrams, and they refuse to shock a rhythm that shouldn't be shocked — which is why bystander use is encouraged.
  • Know your locations. Many camps and public buildings post AED signs; finding the nearest one is part of being prepared.

Official source

AED steps — American Red Cross →

Reflects current Red Cross AED guidance and the 2025 AHA Chain of Survival. This is general information, not a substitute for hands-on training — take a certified CPR/AED course.

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