Iowa Code § 327F.3: Catwalks and handrails.

Any person operating a railroad in this state shall construct and maintain in good repair a catwalk and handrail on at least one side of every railway bridge and trestle which shall be constructed, or the structure of which is renovated in any manner, after January 1, 1976. The catwalk and handrail shall extend the length of the bridge or trestle.