Arizona idling law: the 5-minute rule

What the law says

No owner or operator of a vehicle shall permit the engine of such vehicle to idle for more than five (5) consecutive minutes except as provided in Section 4 (Exemptions) of this ordinance.

Maricopa County Ordinance P-21, Section 3(A)

Who and what it covers

P-21 reaches any device or combination of devices (a tractor with its trailer, a cement mixer, a refrigeration unit) that has a GVWR over 14,000 lbs, must be registered under Arizona law, is designed for public highways and runs on diesel. Maricopa County says it applies to such vehicles operating in the county regardless of where they are registered. The limit counts consecutive minutes, and “idling” means a diesel engine running while not engaged in gear. Gasoline vehicles, and diesels at or under 14,000 lbs, are outside it.

Exemptions

• Vehicle forced to stay motionless by traffic, or by adverse weather affecting safe operation (P-21 §4(A))
• Vehicle operated for emergency or law-enforcement purposes (§4(B))
• Engine driving a power take-off (or equivalent) for loading or unloading, mixing or processing cargo, controlling cargo temperature, or a mechanical work extension (§4(C))
• Idling to meet the manufacturer’s warm-up or cool-down specifications, for maintenance or diagnostics, or for manufacturer research testing (§4(D))
• Commercial passenger and school buses heating or cooling passengers: up to 30 minutes per hour; above 75°F, up to 60 minutes in any 90-minute period (§4(E))
• Idling during federal (49 CFR Part 395) or Arizona (R17-5-202) hours-of-service rest periods (§4(F))

Penalties

ARS §11-876(D) fixes the civil penalty: $100 for a driver’s first violation and $300 for a second or any subsequent violation, and P-21 §3(B) repeats those figures. Citations are written on a uniform civil ticket modeled on a traffic ticket (§11-876(E)), and an officer may issue only one idling citation per traffic stop or investigation (§11-876(F)).

Who enforces it, and how to report

The Maricopa County Air Quality Department administers P-21. Under ARS §11-876(E), a county control officer or any law enforcement officer authorized to enforce traffic laws may cite violators, and P-21 records the Attorney General’s interpretation that any law enforcement officer may enforce it on private or public property.

Maricopa County’s Diesel Idling page sends suspected violations to its online Air Quality Violations Report Form (survey123.arcgis.com/share/2668299450654188a721eb166a5fc581). You can also call the Air Quality Department hotline at 602-372-2703, staffed 8 a.m. to 5 p.m. Monday through Friday with voicemail after hours. The county asks for a single submission per incident (duplicates slow its response), says an inspector may contact you for more information, and publishes complaints in its Air Quality Public Records Viewer, so leave sensitive personal details out of the description.

Local rules in Arizona

• Maricopa County (Phoenix metro): Diesel vehicles over 14,000 lbs GVWR may not idle more than 5 consecutive minutes; civil penalty $100 for a first violation and $300 for a second or subsequent violation. Truck stops and distribution centers must post a permanent sign at least 12 by 18 inches stating the 5-minute limit, the county’s idling information line and the fine. (Maricopa County Ordinance P-21, §§3(A)-(C))

History

ARS §11-876(A) required affected counties to adopt their ordinances by July 1, 2002; Maricopa County adopted P-21 on June 26, 2002.

Reporting in Arizona is unpaid. The only program that pays complainants is New York City's.