If the snow and ice on the sidewalk is frozen so hard that it cannot be removed without injury to the pavement, the owner, lessee, tenant, occupant or the person having charge of any building or lot shall, within the time specified in this article, cause the sidewalk abutting on the premises to be strewn with ashes, sand, sawdust or other similar suitable materials and shall, as soon as the weather shall permit, thoroughly clean the sidewalk. (Ord. Nos. 3314; 19398)