In ten seconds, check for danger to yourself, test whether the person responds, and shout for help — what all help starts with, before any diagnosis.
Read this before you start
What this course does and doesn't do
This course follows the 2025 European Resuscitation Council (ERC) guidelines and is written for adults with no medical training. US courses (American Heart Association, Red Cross) differ in a few details — for example, they start CPR on a child with compressions rather than five breaths; either is far better than doing nothing.
The course doesn't replace hands-on training. Compression depth, hand position, and full chest recoil can only be learned with your hands on a manikin, with an instructor watching. The course gives no individual medical advice and doesn't teach the use of prescription medicines. Nothing in it is a reason to delay calling 911.
In most US states, a bystander may give first aid but isn't required to, and Good Samaritan laws protect anyone who helps in good faith. Calling 911 and staying with the person is already help, and it's enough.
And one rule that outranks everything else in this course: if you're unsure about anything, call 911 and do what the dispatcher tells you. Doubt is not a reason to wait.
Lesson notes
What this course does and doesn't do
This course follows the 2025 European Resuscitation Council (ERC) guidelines and is written for adults with no medical training. US courses (American Heart Association, Red Cross) differ in a few details — for example, they start CPR on a child with compressions rather than five breaths; either is far better than doing nothing.
The course doesn't replace hands-on training. Compression depth, hand position, and full chest recoil can only be learned with your hands on a manikin, with an instructor watching. The course gives no individual medical advice and doesn't teach the use of prescription medicines. Nothing in it is a reason to delay calling 911.
In most US states, a bystander may give first aid but isn't required to, and Good Samaritan laws protect anyone who helps in good faith. Calling 911 and staying with the person is already help, and it's enough.
And one rule that outranks everything else in this course: if you're unsure about anything, call 911 and do what the dispatcher tells you. Doubt is not a reason to wait.
Three actions that come before everything else
The first ten seconds aren't about diagnosis. Nobody expects you to know what's wrong. Do three things, in exactly this order.
Look around. The scene first, then the person. First-aid rules require that nothing at the scene threaten the helper: a helper who gets hurt helps no one — which is why water rescue starts with “don't go in unless you're trained.” Also see how many people are hurt, put on gloves if you have them, and tell the person and those around you that you're going to help (first-aid courses call this getting consent).
Call out. Speak loudly to the person and gently shake their shoulders. If there's no answer or response, treat it as a life-threatening emergency — don't wait for things to get clearer.
Shout for help. Out loud, even if no one seems near: people are usually behind doors and windows. You'll need hands — to bring a defibrillator, open the building's front door, meet the ambulance.
Example: Evening, a kitchen. The man you were just talking to sinks to the floor. You don't rush to feel for a pulse. One second for the floor and stove: nothing spilling or burning, no one else hurt. You lean in: “Can you hear me?” — and shake his shoulders. No answer. You shout into the hallway: “Help! Someone's collapsed — I'm helping him!”
Next comes the call, and it can't wait. Lesson 2 covers how to make it.