Utah Code Ann. § 41-6a-1642
(1) The legislative body of each county required under federal law to utilize a motor vehicle emissions inspection and maintenance program or in which an emissions inspection and maintenance program is necessary to attain or maintain any national ambient air quality standard shall require:
(a) a certificate of emissions inspection, a waiver, or other evidence the motor vehicle is exempt from emissions inspection and maintenance program requirements be presented:
(b) compliance with this section for a motor vehicle registered or principally operated in the county and owned by or being used by a department, division, instrumentality, agency, or employee of:
(2) A vehicle owner subject to Subsection (1) shall obtain a motor vehicle emissions inspection and maintenance program certificate of emissions inspection as described in Subsection (1), but the program may not deny vehicle registration based solely on the presence of a defeat device covered in the Volkswagen partial consent decrees or a United States Environmental Protection Agency-approved vehicle modification in the following vehicles:
(a) a 2.0-liter diesel engine motor vehicle in which its lifetime nitrogen oxide emissions are mitigated in the state pursuant to a partial consent decree, including:
(b) a 3.0-liter diesel engine motor vehicle in which its lifetime nitrogen oxide emissions are mitigated in the state to a settlement, including:
(3)
(a) The legislative body of a county identified in Subsection (1), in consultation with the Air Quality Board created under Section 19-1-106, shall make regulations or ordinances regarding:
(b) The regulations or ordinances shall:
(c) The county legislative body and the Air Quality Board shall give preference to an inspection and maintenance program that is:
(d) The provisions of Subsection (3)(c)(iii) apply only to the extent the phase-out:
(4) The following vehicles are exempt from the provisions of this section:
(b) a motor vehicle that:
(5)
(a) The legislative body of a county identified in Subsection (1) shall exempt a pickup truck, as defined in Section 41-1a-102, with a gross vehicle weight of 12,000 pounds or less from the emission inspection requirements of this section, if the registered owner of the pickup truck provides a signed statement to the legislative body stating the truck is used:
(ii) exclusively for the following purposes in operating the farm:
(6)
(7)
(c)
(v) The notice described in Subsection (7)(c)(iv) shall:
(d) If an emissions inspection is only required every two years for a vehicle under Subsection (7)(c), the inspection shall be required for the vehicle in:
(9)
(11)