ARE THEY DANGEROUS? CAN THEY SHOCK SOMEONE ACCIDENTALLY?

If there is normal heart rhythm, an AED will not allow a shock to be delivered. For example, if a person thinks the casualty is not breathing but the heart is beating, an AED will assess whether there is a heart rhythm and advise by voice command that a shock is not required. The AED is intelligent and it is impossible for it to deliver a shock when not needed.

If someone is in cardiac arrest, in clinical terms, they are already classed as dead, by using an AED you will only be increasing their chances of survival.