If someone is injured in an incident, first check that you and the casualty are not in any danger. If you are, make the situation safe. When it's safe to do so, assess the casualty and dial 999 or 112 for an ambulance (if necessary). You can then carry out basic first aid.

Assessing a casualty

The priorities when dealing with a casualty can be remembered as ABC:

• Airway
• Breathing
• Circulation

Airway

If the casualty appears unresponsive, ask them loudly if they are OK and if they can open their eyes. If they respond, you can leave the casualty in the position they are in until help arrives. While you wait, keep checking their breathing, pulse and level of response:

• Are they alert?
• Do they respond to your voice?
• Do they respond to pain?
• Is there no response to any stimulus (they're unconscious)?

If there is no response, leave the casualty in the position they are in and open their airway. If this is not possible in the position they are in, gently lay them on their back and open the airway.

You open the airway by placing one hand on the casualty’s forehead and gently tilting the head back, then lifting the tip of the chin using two fingers. This is to move the tongue away from the back of the mouth. Do not push on the floor of the mouth as this will cause the tongue to obstruct the airway.

If you think they may have a spinal injury, place your hands on either side of their face and use your fingertips to gently lift the angle of the jaw to open the airway. Take care not to move the casualty’s neck. This is known as the jaw thrust technique.

Breathing

To check if a person is still breathing:

• Look to see if their chest is rising and falling.
• Listen over their mouth and nose for breathing.
• Feel their breath against your cheek for 10 seconds.

If they are breathing, place them in the recovery position so the airway remains clear of obstructions.

If the casualty is not breathing, call 999 or 112 for an ambulance, then begin CPR.

Circulation

If the heart stops beating, you can help maintain their circulation by performing chest compressions. This is cardiopulmonary resuscitation (CPR) when combined with rescue breaths.

If you are not trained or feel unable to give rescue breaths, you can perform compression-only CPR.

Agonal breathing is common in the first few minutes after a sudden cardiac arrest (when the heart stops beating). Agonal breathing is sudden, irregular gasps of breath. This should not be mistaken for normal breathing and CPR should be given straight away.