Medical electrical equipment, why test the residual voltage?

Because some of the inductive components in the electrical equipment may produce a certain amount of induced voltage, and medical electrical equipment involved in the patient's life safety, the person's withstand the safety of the voltage of 36V, so we must ensure that the patient in the use of electrical equipment is not a safety hazard, then the residual voltage of the electrical equipment must not be higher than the residual voltage of 36V, so the residual voltage of the electrical equipment to be tested,