Under no circumstances shall the Board of Zoning Appeals grant an appeal or variance to allow a use not permissible under the terms of this Ordinance in the district involved, or any use expressly or by implication prohibited by the terms of this Ordinance in said district. In granting any appeal or variance, the Board of Zoning Appeals may prescribe appropriate conditions and safeguards in conformity with this Ordinance. Violation of such conditions and safeguards, when made a part of the terms under which the appeal or variance is granted, shall be deemed a violation of this Ordinance and punishable under Section 1107.99.