(a) All signs and supports shall be installed and maintained subject to the following:
(1) Signs and supports shall be structurally sound, safe and pose no danger to persons or property.
(2) Signs and supports shall be fabricated on and of materials which are good quality, good durability and conform to allowable stresses and temperatures for such materials.
(3) Signs and supports shall be structurally designed to withstand a wind force of seventy-five miles per hour.
(4) Electric wiring shall be installed and maintained according to safe practice and in weatherproof condition.
(5) Signs and supports shall not constitute a blight or deteriorating influence on adjacent or neighboring properties.