When it comes to reasons for reducing idling, there are “carrots” and then there are sticks.

States, provinces and municipalities are cracking down on truck idling with new regulations, stricter enforcement of existing limits and hefty fines to drive the point home. Enforcement responsibility rests with a variety of entities, from health officials to the Highway Patrol, but regardless of who is writing the citations, the message is clear: the days of idling legally are drawing to a close.

Here is a brief summary of the idling and smoke emissions requirements currently in place. Virtually every state and municipality regulates vehicle noise, so noise limits are not included here.

  • Alabama: Prohibits the emission of “visible air contaminants from diesel-powered motor vehicles or other movable sources” of a shade or density greater than 20% opacity for longer than five consecutive seconds.
  • Arizona: Regulates smoke emissions and limits idling to five minutes statewide. There are exemptions for traffic conditions, onboard equipment like reefer units and for heat/cooling for drivers sleeping in parked vehicles.
  • California: Regulates smoke emissions statewide. Idling is limited to 30 minutes at marine ports and terminals processing 100,000+ containers per year. Certain municipalities also limit idling. The California Air Resources Board has also announced that it is considering a statewide ban on idling of heavy-duty diesel vehicles. Beginning with model year 2007, idling would be limited to five minutes and vehicles would be required to have a tamper-proof engine idle shutdown device or Alternative Power Unit (APU).
  • Colorado: Regulates smoke emissions statewide. Idling restrictions are also in place within Denver, Aspen and Colorado Springs. There are certain exemptions for low ambient temperatures, emergencies, etc., but not for sleeping in the vehicle.
  • Connecticut: Limits idling to three consecutive minutes. Certain exemptions made for traffic congestion, breakdowns, engine heating at temperatures below 20 degrees F. and the operation of heating, cooling or auxiliary equipment if necessary to accomplish the intended use of the vehicle. Air Management personnel enforce the regulations.
  • District of Columbia: Limits truck idling to three minutes, unless vehicle is powering PTO or ambient temperature is below 32 degrees F. Enforcement is handled by Air Quality Division field officers, metropolitan police, and parking enforcement personnel. Fines are $500 for a first offense, $1000 for a second, $2000 for the third and $4000 for a fourth offense. Other penalties may also apply.
  • Georgia: Idling restrictions are in place for Atlanta.
  • Hawaii: Idling is prohibited statewide, including for powering A/C. There are some very limited exemptions. The Department of Health enforces the regulations. Fines can reach $25,000 per day for each offense.
  • Illinois: Idling is prohibited on business streets statewide for longer periods than are necessary to load/unload.
  • Maryland: Idling is generally limited statewide to five minutes, with some specific exemptions. The State Highway Patrol enforces idling regulations.
  • Massachusetts: Idling is limited statewide to five minutes with certain exceptions. Regulations may be enforced by police, fire, board of health or building inspection personnel. The City of Boston actively enforces anti-idling restrictions with a dedicated anti-pollution enforcement team.
  • Minnesota: The City of Owatonna limits idling on residential streets.
  • Missouri: The City of St. Louis limits truck idling to ten minutes. There is a fine of up to $500 for violations and the possibility of up to 90 days imprisonment.
  • Montana: During periods of poor air quality (as declared by the health dept.) Lewis & Clark County limits idling to two hours in any 12-hour period. The City of Helena limits idling to two hours.
  • Nevada: Regulates smoke emissions statewide and limits idling statewide to 15 minutes except for emergency vehicles, vehicles in traffic congestion, while vehicles are being repaired, for operation of certain specified equipment or when emissions are treated and/or contained by an approved means. Fines are $100 to $500 for a first offense, $500-$1000 for a second, $1,000-$1,500 for the third and $1,500-$2,500 for a fourth offense.
  • New Hampshire: Limits idling statewide to five minutes if the ambient temperature is above 32 degrees F. Limits are extended to 15 minutes when the ambient temperature is between –10 degrees and +32 degrees F. Unlimited idling is permitted if the temperature is below –10 degrees F. “where no nuisance is created.”
  • New Jersey: Limits idling of diesel- or gasoline-powered trucks statewide to three minutes unless the vehicle is at the operator’s place of business, then the limit is 30 minutes. If a vehicle has been stopped for three or more consecutive hours, idling is limited to 15 consecutive minutes. There are specific exemptions, including for operating refrigerator units and PTOs and for truck sleepers in non-residential areas if the driver is sleeping or resting.
  • New Mexico: Regulates smoke emissions statewide, specifically including emissions during idling. Smoke opacity is limited to 30% for no more than ten seconds at altitudes of less than 8,000 ft. or 40% when vehicle is being started.
  • New York: Limits diesel truck idling statewide to five minutes with exemptions for powering certain auxiliary equipment such as PTO’s or cranes or if a truck is motionless for more than two hours and the ambient temperature is below 25 degrees F. Within New York City, idling is limited to three minutes. Anti-idling laws are enforced, generally by the State Highway Patrol.
  • Pennsylvania: Limits diesel truck idling within the City of Philadelphia to two minutes. Trucks may idle for up to five minutes when the ambient temperature is below 32 degrees F. and for up to 20 minutes when the temperature is less than 20 degrees F. Enforcement is by Air Management Services or police department personnel. Fines are $300 per day, per violation with court appearances possible for repeat offenders.
  • Rhode Island: Regulates smoke emissions statewide.
  • Texas: Has local idling limits for diesel trucks in several cities, including Houston and Dallas. In eight counties in the Houston-Galveston area idling is also prohibited for more than five minutes during the months of April through October. There are some exemptions. Fines range from $500-$1,000.
  • Utah: Regulates smoke emissions statewide and limits continuous idling to 15 minutes in Salt Lake, Davis and Utah Counties in the Salt Lake City area. Davis and Utah Counties permit up to 45 minutes of idling in a 120-minute period. There are certain exemptions, including for emergency vehicles, to supply power to refrigeration units and to supply heat/AC to sleeper cabs. In Salt Lake County, environmental, health, police or Highway Patrol officers may issues citations. Fines typically begin at $500 and are determined by the nature of the violation.
  • Virginia: Limits idling to three minutes in commercial and residential areas unless it is to provide power for devices other than for heating or cooling the driver. Diesel trucks may idle up to ten minutes to minimize restart problems. The Department of Environmental Quality enforces idling regulations.
  • Washington: Regulates smoke emissions statewide.
  • British Columbia: Regulates smoke emissions province-wide.
  • Ontario: Regulates smoke emissions province-wide.
NOTE: Information on regulations is drawn from several sources, primarily the Department of Energy and the Environmental Protection Agency.