Roof height means the maximum height of a vehicle (rounded to the nearest inch), excluding narrow accessories such as exhaust pipes and antennas, but including any wide accessories such as roof fairings. Measure roof height of the vehicle configured to have its maximum height that will occur during actual use, with properly inflated tires and no driver, passengers, or cargo onboard. Roof height may also refer to the following categories:
(1) Low-roof means relating to a vehicle with a roof height of 120 inches or less.
(2) Mid-roof means relating to a vehicle with a roof height of 121 to 147 inches.
(3) High-roof means relating to a vehicle with a roof height of 148 inches or more.
40 CFR § 1037.801
The following definitions apply to this part. The definitions apply to all subparts unless we note otherwise. All undefined terms have the meaning the Act gives to them. The definitions follow: