Ind. Code § 8-8-7-2
From and after June 1, 1914, it shall be unlawful, except as otherwise provided in this chapter, for any such common carrier by railroad to use on its line any caboose car, or other car used for like purposes, unless such caboose or other car shall be at least twenty-four (24) feet in length exclusive of the platform and equipped with two (2) four-wheel trucks and said caboose car or other car shall be of constructive strength equal to that of sixty thousand (60,000) pounds capacity freight cars, and shall be provided with a door in each end thereof and an outside platform across each end of said car. Each platform shall not be less than twenty-four (24) inches in width and shall be equipped with proper guard rails and with grab-irons and steps for the safety of persons getting on and off said car. Said steps shall be equipped with a suitable rod, board, or other guard at each end and at the back thereof properly designed to prevent slipping from said step. Said caboose shall have necessary cupola or bay window, closets, and windows.
IC 8-8-7-2