Iowa Code Title VIII. Transportation [Chs. 306-330B] § 321.18. Vehicles subject to registration--exception

1. Any such vehicle driven or moved upon a highway in conformance with the provisions of this chapter relating to manufacturers, transporters, dealers, or nonresidents as contemplated by section 321.53 and chapter 326, or under a temporary registration permit issued by the department as hereinafter authorized.

2. Any such vehicle which is driven or moved upon a highway only for the purpose of crossing such highway from one property to another.

3. Any implement of husbandry.

4. Any special mobile equipment as defined in this chapter.

5. Any vehicle which is used exclusively for interplant purposes, in the operation of an industrial or manufacturing plant, consisting of a single unit comprising a group of buildings separated by streets, alleys, or railroad tracks, and which vehicle is used solely to transport materials from one part of the plant to another or from an adjacent railroad track to the plant and in so doing incidentally using said streets or alleys for not more than one thousand feet.

6. Any vehicle which is propelled by electric power obtained from overhead trolley wires, but not operated upon rails.

7. Any school bus in this state used exclusively for the transportation of pupils to and from school or a school function or for the purposes provided in section 285.1, subsection 1, and section 285.10, subsection 9, or used exclusively for the transportation of children enrolled in a federal head start program. Upon application the department shall, without charge, issue a registration certificate and registration plates. The plates shall be attached to the front and rear of each bus exempt from registration under this subsection.

8. Any mobile home or manufactured home and any temporary undercarriage used solely for transporting manufactured homes, modular homes, or other portable buildings used or intended to be used for human occupancy.

9. Any trailer that is used exclusively for the transportation, display, and distribution of flags honoring deceased veterans in parades or ceremonies held on Memorial Day, Veterans Day, or other patriotic occasions as authorized by resolution of the local government of the community where the parade or ceremony takes place. A trailer exempt from registration under this subsection shall only be used on city streets or secondary roads on the day of a parade or ceremony specified in the local government's resolution, and a copy of the resolution shall be carried at all times in the vehicle pulling the trailer.