An electrical device such as this requires reverse leakage current of 100nA @ 10V.During operation, the maximum voltage - Zener (Nom) is reduced to 13V volts.
GDZ13B-HG3-18 Features
reverse leakage current of 100nA @ 10V 100nA @ 10V is the maximum voltage (Tol)
GDZ13B-HG3-18 Applications
There are a lot of Vishay Semiconductor Diodes Division GDZ13B-HG3-18 applications of zener single diodes.