An electrical device like this requires a reverse leakage current of 5μA @ 18.2V.While the device is operating, the maximum voltage - Zener (Nom) is reduced to 24V.
SML4749AHE3_A/I Features
reverse leakage current of 5μA @ 18.2V 5μA @ 18.2V is the maximum voltage (Tol)
SML4749AHE3_A/I Applications
There are a lot of Vishay Semiconductor Diodes Division SML4749AHE3_A/I applications of zener single diodes.