15.44.160   Demolition restrictions.
   A permittee shall not operate any equipment, demolish any building or structure, or remove any material from a building or structure on the traffic side of a pedestrian canopy or walkway which results in the equipment operating over the top of the canopy or walkway. The use of a "headache" ball or any other battering device on the exterior walls of any building or structure is prohibited when such device will swing or be swung over public property or when, through its use, it will cause structural material to fall or be propelled onto public property. The director may prohibit the use of any such device on any portion of any building, when in his or her opinion, its use will create a hazard to public property.
   When wrecking or demolishing any building of three or more stories, the permittee shall remove one story therefrom at a time commencing with the roof. No floor shall be removed until the exterior wall above that floor has been removed.
   No explosive of any kind shall be used to demolish any portion of any building or structure without the express approval of the city council.
   If it is necessary to use public property for the storage of structural material, only that portion between the pedestrian walkway and the building shall be so used. Any structural material removed from the building or structure shall be low-ered to the ground immediately. No structural material shall be purposely dropped onto public property. (Prior code § 9.10.405)