If you do need to use one, call 999. The 999 call handler will know where the closest defibrillator is and will be able to give you a code to access it.
To find the nearest location, please visit https://www.defibfinder.uk/
A defibrillator is a device that gives a high energy electric shock to the heart of someone who is in cardiac arrest. This high energy shock is called defibrillation, and it's an essential part in trying to save the life of someone who’s in cardiac arrest. A defibrillator may also be called a defib, an AED (Automated External Defibrillator) or a PAD (Public Access Defibrillator).
You don't need to be trained to use a defibrillator; there are clear instructions, anyone can use one.