You can use an AED with no training. The machine analyses someone’s heart rhythm and then uses visual or voice prompts to guide you through each step.

• First, make sure someone has called for an ambulance, and, if an AED isn’t immediately available, give CPR (cardiopulmonary resuscitation) until someone can bring you an AED.

• As soon as you’ve got an AED, switch it on. It will immediately start to give you a series of visual and verbal prompts informing you of what you need to do. Follow these prompts until the ambulance arrives or someone with more experience than you takes over.