321.453  Exceptions.
  1.   Except as provided in sections 321.463, 321.471, and 321.474, the provisions of this chapter governing size, weight, and load and the permit requirements of chapter 321E do not apply to any of the following:
  a.  Fire apparatus.
  b.  Road maintenance equipment owned by, under lease to, or used in the performance of a contract with any state or local authority.
  c.  Implements of husbandry when moved or moving upon a highway that is not a portion of the interstate.
  d.  Equipment used primarily for construction of permanent conservation practices on agricultural land when moved or moving upon a highway that is not a portion of the interstate, so long as the equipment is without payload and the movement does not violate posted weight limitations on bridges.
  e.  Hydroexcavation equipment used primarily for digging and excavation when moved or moving upon a highway that is not a portion of the interstate.
  2.  A vehicle that is carrying an implement of husbandry or equipment used primarily for construction of permanent conservation practices and is exempted from the permit requirements under this section shall be equipped with an amber flashing light visible from the rear. If the amber flashing light is obstructed by the loaded implement or equipment, the loaded implement or equipment shall also be equipped with and display an amber flashing light. The vehicle shall also be equipped with warning flags on that portion of the vehicle which protrudes into oncoming traffic, and shall only operate from thirty minutes prior to sunrise to thirty minutes following sunset.
  3.  A motor vehicle that is operated by a farmer and that is carrying an implement of husbandry between fields, locations for repair, or locations for storage of the implement of husbandry shall be exempt from any requirement to obtain a permit under section 321.463, 321.471, or 321.474. Nothing in this subsection shall be construed to exempt such a vehicle from any requirement or restriction other than a requirement to obtain a permit, including but not limited to requirements or restrictions relating to size, weight, load, lighting, flags, equipment, or manner of operation. For the purposes of this subsection, “farmer” means as defined in section 142D.2.
[C39, §5035.02; C46, 50, 54, 58, 62, 66, 71, 73, 75, 77, 79, 81, §321.453; 82 Acts, ch 1154, §3, ch 1254, §3]
86 Acts, ch 1210, §6; 87 Acts, ch 186, §4; 94 Acts, ch 1087, §3; 94 Acts, ch 1198, §45; 98 Acts, ch 1003, §1; 98 Acts, ch 1223, §26; 99 Acts, ch 13, §18; 99 Acts, ch 108, §6; 2014 Acts, ch 1087, §1, 2; 2015 Acts, ch 30, §104; 2017 Acts, ch 81, §1; 2023 Acts, ch 6, §1
Referred to in §321.423, 321E.2