CPR When You’re Not a Professional
Someone in cardiac arrest has minutes. Their chance of survival falls with every one of them, and the person most likely to be standing there is not a paramedic — it is whoever happens to be in the room.
Which makes bystander CPR the highest-impact skill on this entire site. And the thing that stops people is almost never technique. It is hesitation: fear of doing it wrong, fear of hurting them, fear of touching a stranger’s chest.
The guidance on that is unambiguous. Someone not breathing normally is already in the worst possible situation. You cannot make it worse by starting.
The emergency numbers in this guide are Australian. If you are somewhere else, call your own country’s emergency number instead — 911 in the United States and Canada, 999 in the United Kingdom, 112 across Europe and on most mobile phones worldwide. The advice itself applies wherever you are.
The 10-minute version
- Not responding and not breathing normally? Start compressions. Call 000 first or get someone else to, then push.
- Rate 100–120 a minute, depth at least one third of the chest, and let the chest come all the way back up between compressions.
- If you will not or cannot do rescue breaths, do compressions only. Australian guidance is that all rescuers perform chest compressions for anyone not breathing normally; rescue breaths are for those trained and willing.
The sequence
1. Danger. Is it safe to approach? Traffic, electricity, water.
2. Response. Talk to them, squeeze their shoulders. “Can you hear me? Open your eyes.”
3. Send for help. Call 000 and put the phone on speaker so the operator can guide you. Ask someone to find a defibrillator.
4. Airway. Tilt the head back gently, lift the chin.
5. Breathing. Look, listen, feel for up to 10 seconds. Occasional gasping is not normal breathing — this is called agonal breathing, it looks like breathing to a frightened bystander, and mistaking it for life is a common reason CPR is not started.
6. CPR. If they are not breathing normally, start compressions: – Heel of one hand in the centre of the chest, other hand on top, fingers interlocked – Arms straight, shoulders over your hands – Push at least one third of the depth of the chest – Rate 100–120 a minute – Allow complete recoil between compressions — leaning on the chest between pushes reduces effectiveness – 30 compressions, then 2 breaths, if you are trained and willing. Otherwise continuous compressions
7. Defibrillation. If a defibrillator arrives, turn it on and follow the voice prompts. They are designed for untrained users and will not shock someone who does not need it.
8. Keep going until the ambulance arrives, they start breathing normally, or you physically cannot continue. Swap with someone else every two minutes if you can — good CPR is exhausting and quality falls off fast.
The numbers
| Element | The number |
|---|---|
| Compression rate | 100–120 per minute |
| Compression depth | At least one third of chest diameter |
| Recoil | Complete, between every compression |
| Ratio (trained and willing) | 30 compressions : 2 breaths |
| Ratio (untrained or unwilling) | Continuous compressions, no breaths |
| Rescuer swap | Every 2 minutes, if someone else is available |
| Breathing check | Up to 10 seconds |
| When to stop | Ambulance takes over, normal breathing returns, or you cannot continue |
On rate: 100–120 a minute is roughly two compressions a second. Many people use a familiar song to keep time — anything at that tempo works, and the ambulance operator on speaker will count with you.
Children and babies
The principles hold; the mechanics scale down.
- Children: one or two hands, still at least one third of chest depth.
- Infants under one: two fingers in the centre of the chest.
- Rescue breaths matter more in children, because paediatric arrests are more often caused by a breathing problem than a heart problem. If you are willing, give breaths.
- Still start compressions if you will not give breaths. Compressions alone remain far better than nothing.
What actually goes wrong
Nobody starts. The single biggest cause of poor outcomes, and it is fear rather than ignorance.
Agonal gasping is mistaken for breathing. Occasional noisy gasps in an unresponsive person mean start CPR.
Compressions are too shallow. Effective CPR is more forceful than people expect. Cracked ribs are a survivable complication; not being resuscitated is not.
Leaning on the chest between compressions, preventing recoil.
Long pauses to check for a pulse, reposition, or discuss. Minimise interruptions.
Waiting for a defibrillator rather than starting compressions immediately.
One person does it all, gets exhausted at four minutes, and the quality collapses.
Nobody looks for an AED. They are in shopping centres, gyms, sports clubs, offices, train stations and increasingly on street registers.
Thresholds
| Situation | The rule |
|---|---|
| Unresponsive, not breathing normally | Call 000, start compressions |
| Occasional gasps | Not normal breathing. Start CPR |
| Untrained or unwilling to give breaths | Compressions only, continuously |
| Defibrillator available | Turn it on, follow the prompts. It will not shock someone who does not need it |
| Two or more rescuers | Swap every 2 minutes |
| Any doubt about whether to start | Start. Someone not breathing normally cannot be made worse |
What it costs
| Tier | Spend | What it buys |
|---|---|---|
| Free | $0 | Knowing the rate, the depth, and that compressions-only counts. Knowing where the nearest AED is |
| Free | $0 | The 000 operator will talk you through it in real time, on speaker |
| Best value on this site | ~$150–250 | A hands-on CPR or first aid course, refreshed every three years. Practising the depth on a manikin is the part reading cannot give you |
| Community | $2,000–4,000 | A defibrillator for a club, workplace or remote property. Genuinely life-saving equipment in a place where an ambulance is far away |
The drill: two minutes now
- Find your nearest defibrillator. Ambulance services and several apps maintain registers. Look up the two places you spend most time — home and work.
- Say the numbers out loud: 100–120 a minute, one third depth, 30:2 or compressions only.
- Practise the tempo by tapping it out for thirty seconds. It is faster than most people assume.
- Practise the position on a cushion: heel of hand centre of chest, arms straight, shoulders over hands.
- Book the course. This is the one item on this whole site where the hands-on version is meaningfully better than reading.
Frequently asked questions
How fast and how deep should CPR compressions be?
100 to 120 compressions a minute, at a depth of at least one third of the chest, allowing the chest to recoil completely between compressions.
What is the CPR ratio?
Thirty compressions to two breaths if you are trained and willing to give rescue breaths. If you are not, do continuous compressions — Australian guidance is that all rescuers should perform compressions for anyone not breathing normally.
Can I do CPR without giving mouth-to-mouth?
Yes. Compression-only CPR is explicitly supported for rescuers who are untrained or unwilling to give breaths, and it is vastly better than doing nothing.
What if the person is gasping?
Occasional gasping in an unresponsive person is not normal breathing — it is agonal breathing, and it means you should start CPR. Mistaking it for life is a common reason bystanders hesitate.
Will I get in trouble if I do it wrong?
Someone who is not breathing normally is already in the worst possible position, and you cannot make that worse by starting. Broken ribs are a survivable complication of effective compressions; not being resuscitated is not.
How do I use a defibrillator?
Turn it on and follow the spoken prompts. They are designed for untrained members of the public and will not deliver a shock to someone whose rhythm does not need one.