If you are not alone, send someone to call for help as soon as you have checked their breathing. Ask the person to come back and confirm that the call has been made.

Make sure the casualty is lying on his back on a firm surface. Kneel beside him and place the heel of your hand on the centre of the chest.

Keeping your arms straight, cover the first hand with the heel of your other hand and interlock the fingers of both hands together. Keep your fingers raised so they do not touch the casualty’s chest or ribcage.

Lean forward so that your shoulders are directly over the casualty’s chest and press straight down on the chest about 4–5cm. Release the pressure, but not your hands and let the chest come back up. Repeat to give 30 compressions at a rate of 100 compressions per minute.

Move to the casualty’s head. Tilt his head and lift his chin to open the airway again. Let his mouth fall open slightly.

Pinch the nostrils closed with the hand that was on the forehead and support the casualty’s chin with your other hand.

Take a normal breath, put your mouth over the casualty’s and blow until you can see his chest rise.

Remove your mouth from the casualty’s and look along the chest, watching the chest fall. Repeat steps 5 and 6 once.

Place your hands on the chest again and repeat the cycle of 30 chest compressions, followed by two rescue breaths. Continue the cycle.

Continue giving CPR until emergency help arrives; the casualty starts to breathe normally; you are too tired to keep going.

If normal breathing begins at any point, place him in the Recovery Position and await help.

Give CPR while you wait for the AED. If there is no one available trained in its use, follow the machine’s instructions.

Switch on AED. Position pads against the skin as shown on the pack.

Stand away from the casualty and make sure that no one is touching him while the AED is analysing. It will tell you as to whether or not a shock is advised.

If shock advised: Make sure no one is touching the casualty and stand clear. Press the shock button; the casualty will ‘jump’. Continue CPR for two more minutes, then the AED will re-analyse the casualty. Follow instructions. Leave pads attached if casualty recovers.

If no shock advised: Continue CPR for two more minutes, then the AED will re-analyse the casualty. Leave pads attached and keep following the AED’s instructions.

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