HB 2439
Initials PAB/AH Page 1 Caucus & COW
ARIZONA HOUSE OF REPRESENTATIVES
Fifty-sixth Legislature
First Regular Session
House: NREW DP 10-0-0-0
HB2439: vehicle emissions inspections; enactment date
Sponsor: Representative Griffin, LD 19
Caucus & COW
Overview
Changes, from July 1, 2023 to July 1, 2027, the date by which the United States Environmental
Protection Agency (EPA) must approve 2021 legislative modifications to vehicle emissions testing
program protocols for them to take effect.
History
The Clean Air Act (CAA) requires the EPA to set National Ambient Air Quality Standards (NAAQS)
for pollutants that are common in outdoor air, harmful to health and the environment and come
from diverse sources (42 U.S.C. § 7409). These pollutants include sulfur dioxide, particulate
matter, nitrogen dioxide, carbon monoxide, ozone and lead. Each state must establish a state
implementation plan (SIP) with measures to maintain NAAQS. The SIP must receive EPA
approval (42 U.S.C. § 7410). Additionally, states with nonattainment areas must develop plans
for these areas to reach an acceptable standard (42 U.S.C. § 7502).
The CAA sets requirements for vehicle inspection and maintenance (I/M) programs to identify and
repair high emissions vehicles and improve air quality in areas that are not meeting NAAQS for
ozone and/or carbon monoxide. I/M programs must follow several federal requirements that
include performance standards, test procedures and standards and data analysis and reporting
standards. However, the degree of testing and inspection for an I/M program increases with the
level of nonattainment. For example, a serious level of nonattainment requires a state to adopt an
enhanced I/M program that requires annual emissions testing and inspection of emissions control
diagnostic systems (42 U.S.C. § 7511a and 42 U.S.C. § 7512a). To receive EPA approval, a
state's SIP must explain how it will achieve I/M program requirements (40 C.F.R. § 51.372). A
SIP remains effective until the EPA approves a revision that convincingly demonstrates the area
can maintain the relevant standards without the emission reductions attributable to the I/M
program (40 C.F.R. § 51.350(c)).
Enhanced I/M programs are currently operated in the Phoenix and Tucson metropolitan areas
due to nonattainment of two NAAQS. Portions of these areas were previously designated as
nonattainment areas under the carbon monoxide NAAQS. The Phoenix metropolitan area
remains designated as nonattainment for the ozone NAAQS. These enhanced I/M programs are
run through the Arizona Department of Environmental Quality's (ADEQ) Vehicle Emissions
Inspection and Maintenance Program (A.R.S. § 49-541 et seq.). In 2021, the Legislature adopted
changes to this program that included revised emission standards for different classes of vehicles
based on features such as the presence of an onboard diagnostic system and use of diesel fuel
(Laws 2021, Chapter 27). However, these changes would only be effective if the EPA's approved
the SIP containing these changes by July 1, 2023. The EPA has not yet responded to the
proposed SIP changes.
HB 2439
Initials PAB/AH Page 2 Caucus & COW
Provisions
1. Extends the date by which the EPA must approve of modifications to vehicle emissions testing
program protocols in order for them to become effective. (Sec. 1)
2. Contains an emergency clause. (Sec. 2)
3. Makes technical changes. (Sec. 1)
☐ Prop 105 (45 votes) ☐ Prop 108 (40 votes) ☒ Emergency (40 votes) ☐ Fiscal Note