Cardiac electrodes and safe voltage limits.

The 5-mV safe voltage limit that has been proposed for hospital safety codes is shown to be based on incorrect assumptions. The actual voltage threshold for 60-Hz current is of the order of 100 mV or greater, because of the effects of electrode interface impedance and cell membrane characteristics. AK value of 50 mV is proposed as the safe voltage limit for 60 Hz current for the purposes of safety standards. The medical community is requested to consider this value.