Nonskid Metallic Tread

The upper, horizontal part of a step upon which the foot is placed, or a section placed upon or set into a deck, walkway, or coaming, made of metal, and corrugated or otherwise specially constructed to resist skidding. May have added material or inserts such as wood strip or abrasive particles to prevent sparking. Excludes door saddle, floor plates, gratings and elevator sills.