IEC 60601-2-4

The particular standard for cardiac defibrillators (manual and AED). It adds to IEC 60601-1 what matters for a device that delivers energy into a patient. What engineers test against it: delivered energy into 50 Ω within ±15% or ±3 J of the selected energy, whichever is greater; charge time to maximum energy within 15 s, including with a battery depleted by 15 maximum-energy discharges; synchronised cardioversion delivering within 60 ms of the R-wave marker; defibrillation-proof applied parts on the ECG input; and, for AEDs, rhythm recognition that advises a shock on shockable rhythms. Rising charge time is the earliest sign of an ageing battery or capacitor.

A summary written by BMEssentia for learning, not the text of the standard. Always work from the current official edition and the manufacturer's instructions.