Every person operating a public transportation system within the City employing motor buses, trackless trolleys, trains or street cars, shall remove and clear away, or cause to be removed and cleared away, snow and ice from its passenger loading and unloading areas and its tracks, if any. Snow and ice from its passenger loading and unloading areas shall be removed and cleared away within the first eight hours of daylight after the cessation of any fall of snow, sleet or freezing rain, except that if the snow and ice has become so hard that it cannot be removed without the likelihood of damage to the underlying surface, such operator shall within the eight-hour period, cause enough sand or other abrasive to be put on the passenger loading and unloading area to make walking thereon reasonably safe. He shall then, as soon thereafter as weather permits, cause such area to be thoroughly cleaned.