Colorado idling law: the 5-minute per hour rule

What the law says

The owner or operator of a covered vehicle shall not cause or permit the vehicle to idle for more than five minutes within any sixty-minute period except as authorized by subsection (2) of this section.

CRS §42-14-105(1)

Who and what it covers

The state standard covers only commercial diesel vehicles with a GVWR greater than 14,000 lbs that are designed to operate on highways (§42-14-104(1)(a)); gasoline vehicles and passenger cars are outside it. The five minutes are a total within any sixty-minute period. Liability falls on the vehicle’s owner or operator and, where a local ordinance covers loading locations, on the owner of the place where the truck loads or unloads (§42-14-106).

Exemptions

• Stopped by highway traffic, a traffic control device or signal, or a law enforcement officer’s direction (§42-14-105(2)(a))
• Running defrosters, heaters or air conditioners, or installing equipment, only to prevent a safety or health emergency and not for rest periods (b)
• Law enforcement, emergency, public safety or military vehicles responding to or training for an emergency (c)
• Required maintenance, servicing or repair (d), and a local, state or federal inspection that requires idling (e)
• Power take-off equipment needed for work-related mechanical or electrical equipment (f)
• Armored vehicles while a guard is inside or during loading and unloading (g)
• Passenger buses: up to five minutes in any sixty-minute period for passenger comfort while non-driver passengers are on board (h)
• Sleeper-berth heat or cooling during a rest or sleep period at a safety rest area, fleet trucking terminal, commercial truck stop or state-designated rest location (i), or at any legal parking spot at least 1,000 feet from residential housing, a school, a daycare, a hospital, a senior citizen center or a medical outpatient facility (j)
• Up to twenty minutes in any sixty-minute period when the ambient temperature is “less then ten degrees” (k, as printed)
• Critical service or utility providers performing their duties (l)

Penalties

Under CRS §42-14-106, a vehicle owner or operator, or the owner of a loading location, who violates the article commits a class B traffic infraction: a fine of not more than $150 for a first offense, not more than $500 for a second or subsequent offense, plus a $20 surcharge under §24-4.1-119.

Who enforces it, and how to report

A violation is a class B traffic infraction, so it is cited like other traffic infractions. Local governments may enact their own idling laws for covered vehicles that are at least as stringent as the state standard, and the state’s exemptions automatically apply to those local laws (§42-14-103). Loading locations are covered only where a local government has adopted a consistent ordinance (§42-14-104(1)(b)), and ordinances in places averaging over 6,000 feet of elevation that were in effect on January 1, 2011 are not superseded (§42-14-104(2)).

The statute names no complaint agency; because the violation is a traffic infraction, report a truck idling past the limit to the police department or sheriff’s office where it is parked, using the non-emergency line. In Denver, the city’s own idling rule sits in its air pollution chapter, and civil penalties under it are set by the manager of the Department of Public Health and Environment (DRMC §4-9).

Local rules in Colorado

• Denver: No person may allow any vehicle to idle more than five minutes in any one-hour period unless the outside temperature has been below 20°F for every hour of the previous 24 hours, or the latest hourly temperature is below 10°F. Exempt: emergency and traffic-control vehicles, vehicles being serviced, vehicles running auxiliary equipment such as pumps, compressors or refrigeration units, and vehicles stopped in traffic. For transportation vehicles designed to carry at least 16 people, active passenger loading time does not count. Penalty: a civil penalty of not more than $2,000 per violation per day under the chapter’s penalty section (§4-9(a)). (Denver Revised Municipal Code §4-43; §4-9(a))

History

The State Idling Standard was enacted by HB11-1275, effective July 1, 2011. HB24-1341, signed April 29, 2024 and effective August 7, 2024, rewrote §42-14-103 so that local governments, which previously could not adopt more stringent rules, may adopt rules at least as stringent as the state’s, and amended the sleeper-berth and cold-weather exemptions while adding the utility-provider exemption.

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