Colorado > Laws and Regulations
Idle Reduction Requirement - Denver, CO
Idling of any vehicle for more than five minutes in any one-hour period is prohibited within the city and county of Denver. Exemptions include the following: when ambient outside air temperatures have been less than 20 degrees Fahrenheit for the previous 24 hours; current ambient outside air temperature are less than 10 degrees Fahrenheit. This requirement does not apply to emergency vehicles, vehicles engaged in traffic operations, vehicles being serviced, vehicles that must idle to operate auxiliary equipment, and vehicles that are idle due to traffic congestion. For more information, see the Denver Environmental Assessment and Policy Idling Vehicles website.