AEDs are portable devices that provide defibrillation in an OHCA setting. They are often placed in public areas where cardiac arrests are likely to occur. Locations such as train stations, shopping malls, airports, athletic events, and the workplace are places where you might expect a crowd to gather.

The rescuer must apply an AED to infants and children with witnessed cardiac arrest as soon as possible. During single rescuer CPR, if cardiac arrest is unwitnessed, the rescuer performs 2 minutes or 5 CPR cycles before leaving the scene to retrieve an AED. If the cardiac arrest is witnessed, the single rescuer should retrieve an AED immediately. When there are two or more rescuers, one leaves the scene immediately to call for help and find an AED. 

An AED with a pediatric dose attenuating system must be used whenever possible for children < 8 years old. If it is not available, then the adult AED may be used.