Children’s Environmental Health in Michigan

Respiratory Health and Asthma: Diesel Exhaust

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This section provides background information and a review of Michigan’s policies related to diesel control technology requirements, diesel vehicle idling, and school bus pollution. Best policy practices from other states will be highlighted, and recommendations to further protect children’s health from diesel exhaust in Michigan will be provided.

Background Information

Sources and Types of Diesel Exhaust

Diesel exhaust is a complex mixture of hundreds of different gases and particles. Common gases found in diesel exhaust include carbon dioxide, carbon monoxide, nitrogen and sulfur compounds, and numerous low-molecular-weight hydrocarbons (such as aldehydes and polycyclic aromatic hydrocarbons which are both linked to toxic health effects) (EPA 2002). The particles found in diesel exhaust are considered to be fine (< 2.5 micrometers in diameter) or ultrafine (< 0.1 micrometers in diameter). These particles are efficient at adsorbing (accumulating on their surfaces) potentially toxic organic compounds due to their collective large surface area. In addition, their small size allows them to travel deep into the lungs (EPA 2002). Fine particles have been shown to have stronger respiratory effects in children than larger, coarse particles that are not deposited as deeply in the lungs (AAP 2003).

In addition being associated with the development and exacerbation of asthma and other chronic respiratory conditions, there is a growing body of evidence that diesel exhaust exposure is potentially associated with the development of lung cancer and cardiovascular problems (Hesterberg et al 2009). While these are important health effects of exposure to diesel exhaust, they are outside of the scope of this report.

The composition of diesel exhaust varies with engine type, fuel composition, and operating conditions. Major on-road sources of diesel exhaust include school buses and diesel trucks. Major off-road sources of diesel exhaust include locomotives, marine vessels, and heavy-duty equipment (EPA 2002).

Childhood Exposure to Diesel Exhaust

Children are primarily exposed to diesel exhaust through direct inhalation of emissions from the sources of diesel exhaust listed above. In particular, inhalation of diesel exhaust from school bus emissions is a primary exposure route for children ¬¬– the U.S. Environmental Protection Agency (EPA) notes that school buses create “microenvironmental exposures of significant concern” (EPA 2002). Children who reside near highways or sites where diesel truck transportation or idling is common may also have a higher exposure to diesel exhaust.

Children’s Exposure to Diesel Exhaust in the U.S

An important route of exposure for children in the U.S. is inhalation of diesel exhaust emissions from school buses. Most school buses in the United States use diesel fuel, and these buses drive more than 4 billion miles per year (EPA 2007a). Children in the U.S. take nearly 10 billion school bus rides every year (Wargo 2002). The EPA estimates that 24 million children in the U.S. ride school buses each day, spending an average of 1.5 hours in the bus daily (EPA 2007a). On the school bus, children are exposed to approximately four times more diesel exhaust than during a car ride (AAP 2003) and on average school buses produce twice as much soot per mile as tractor trucks (UCS 2006). Several recent studies show that children in school buses can be exposed to levels of diesel particulate matter up to ten times higher than levels outside the bus (Wargo 2002). Engine age has shown to be a major determinant of the concentrations. A study in south Texas found that the average total particle concentrations inside of 1990 model year school buses to be 4.6 times those inside of 2006 model year buses (Zhang & Zhu 2010). Furthermore, outdoor air pollution around school bus stops has been associated with the volume of bus traffic (Li et al. 2009, Patel et al. 2009). One study in New York found that the majority of the effect of bus and truck traffic on black carbon in the air around schools was due to bus and truck engine idling (Richmond-Bryant et al. 2011).

In 2005, school buses in the U.S. released an estimated 3,700 tons of particulate matter and 101,000 tons of smog-forming pollutants such as nitrogen oxides (NOx) and non-methane hydrocarbons (UCS 2006). The idling of school buses is a significant source of diesel pollution at schools, and can pollute the air in and around the bus. The exhaust can also enter school buildings through windows, doors, and air intakes, thus increasing overall exposure for school children (EPA 2007a).

Children’s Exposure to Diesel Exhaust in Michigan

In 2006, the Union of Concerned Scientists (UCS) estimated that Michigan buses were on average 10 years old, with 40% of the fleet over 10 years old, and released 15.9 pounds of soot and 411 pounds of smog forming pollution per bus (UCS 2006). Michigan received a “C” grade from the Union of Concerned Scientists (UCS 2006) for its overall soot pollution stemming from school buses, and its soot prevention programs were deemed “poor.” In fact, the UCS estimated that only 0.5% of school bus soot had been reduced through Michigan’s clean-up efforts (UCS 2006).Respiratory Health Impacts and Diesel Exhaust

Numerous studies have found a link between acute exposure to diesel exhaust and acute irritation of the eyes, throat, and respiratory tract, as well as other acute respiratory symptoms (such as cough and phlegm). Studies show that there is a link between acute diesel exhaust exposure and exacerbation of asthma and reaction to allergens. Because of this, diesel exhaust exposure can adversely affect people with underlying respiratory illnesses such as asthma, bronchitis, and infections (Wargo 2002). This is especially true in children, as children’s airways are not yet fully developed and have a smaller diameter than those of adults. If a child’s airways are inflamed or constricted by asthma, allergies or infections, exposure to diesel exhaust may exacerbate the child’s condition and make breathing more difficult (Wargo 2002). Diesel emissions may also enhance the effects of some allergens among sensitive individuals—diesel exhaust particles may enhance allergic and inflammatory responses and may even facilitate the development of new allergies (AAP 2003).

Many human epidemiological studies have been conducted to examine long-term health impacts associated with childhood exposure to diesel exhaust. The results of some of these studies are presented below:

  • A study of children residing in Erie County, New York, found that those children living in neighborhoods with heavy truck traffic had higher rates of asthma hospitalizations (Lin et al. 2002).
  • Children exposed to higher levels of traffic pollution were more likely to experience wheezing, ear, nose, and throat infections, and be diagnosed with asthma by the age of two. The study took place in the Netherlands and followed 4,000 children from birth until two years of age (Brauer et al. 2002).
  • Exposure to traffic-related pollution, especially diesel exhaust particles, may be related to reduced lung function in children living near major roadways, according to a study of children living in six different areas in the Netherland. The researchers also measured air pollution in schools and found that lung function of children was significantly associated with levels of black smoke (a proxy for diesel exhaust) measured inside the schools (Brunekreef et al. 1997).
  • A recent study found an association between the diagnosis of physician-diagnosed new-onset asthma in children (as reported by their parents) and the amount of traffic-related pollution children were exposed to at home and at school (McConnell et al. 2010).

Policy Summary and Analysis

Diesel Emissions Control and Exposure Control Technologies – Retrofits

There are a variety of technologies on the market which can decrease both the amount of particulate matter emissions from vehicles’ exhaust pipes as well as decrease the amount of exhaust which enters the cabin of vehicles (self-pollution). While some newer diesel engines are already outfitted with some of these technologies, older and newer engines can be retrofit in order to reduce the amount of pollutants emitted by the vehicle.

  • Diesel oxidation catalysts (DOCs): These devices treat diesel exhaust to reduce emissions and are widely used as retrofit technologies because they require relatively little maintenance. Generally, DOCs use a honeycomb structure coated in platinum or other precious metals. The catalytic process that the exhaust is exposed to while being funneled through the honeycomb structure breaks down certain pollutants (such as NOx and SOx) into less harmful substances (EPA 2013a).
  • Diesel Particulate Filters (DPFs): DPFs are devices which treat diesel exhaust by using a porous ceramic, cordierite, or metallic filter to remover particulate matter (PM) from the exhaust stream of the vehicle. This PM is then reduced to ash when the filter element reaches a temperature high enough for it to combust. Regular maintenance is required to remove non-combustible filtered materials (EPA 2013a).
  • Partial Diesel Particulate Filters (pDPFs): These devices, also known as flow-through filters work similarly to DPFs, but provide a more moderate reduction of PM from diesel exhaust (EPA 2013a).
  • Selective Catalytic Reduction (SCR): SCR devices inject diesel exhaust fluid (DEF) into the exhaust stream of diesel engines which reacts with a catalyst to reduce NOx emissions into harmless nitrogen and oxygen gases. These systems require periodic refilling of the DEF. Most engines manufactured after 2009 have SCR systems in place due to new federal NOx standards for diesel engines (EPA 2013a).
  • Closed Crankcase Ventilation (CCV): CCV systems reduce crankcase emissions, which are released directly into the atmosphere from the engine. CCV systems capture the oil in “blow-by” gas, which is released from the engine, and redirect it to the intake system to be combusted; normally this would be released. Most engines manufactured since 2007 use CCV systems (EPA 2013a).
  • Exhaust Gas Recirculation (EGR): EGR devices work to reduce the production of NOx by recirculating exhaust back to the engine block, cooling it and reducing the peak combustion temperatures which in turn reduces the production of NOx, as NOx is generally produced in combustion under particularly high temperatures. Because this technology requires major reworkings of the engine, its use as a retrofit isn’t common (EPA 2013a).
  • Lean NOx Catalysts (LNCs): LNCs create a catalytic reaction to reduce NOx emissions by using diesel fuel injected into the exhaust stream. Unfortunately, the use of this mechanism also means that LNC-equipped vehicles can have 5-7 percent higher fuel usage than comparable vehicles which are not LNC-equipped (EPA 2013a).

Idling Reduction Equipment

An average idling diesel engine will consume approximately 1 gallon of gas per hour. As such, methods to reduce idling can save both fuel as well as prevent the emission of harmful pollutants both into the atmosphere and inside of the cabins of trucks and buses.

Equipment that facilitates reductions in idling:

  • Electrified Parking Spaces (EPS) / Truck Stop Electrification (TSE): These systems can supply heating, cooling, and electrical power to trucks and buses, reducing idling by providing an alternative source of electricity aside from the engine and battery of the vehicle (EPA 2013b).
  • Auxiliary power units and generator sets (APU/GS): These units allow users of large diesel vehicles (ex. buses, trucks) to heat the cabins of the vehicle without idling the vehicles’ engine. Instead, these generators are powered by smaller, EPA emission-certified engines (EPA 2013b).
  • Battery Air Conditioning Systems (BAC): These systems use battery-power to provide air conditioning to the cabin without running the engine (EPA 2013b).
  • Engine Block Pre-Heaters are used to heat the engine block for a warm start. Each block pre-heater uses only 1/2 cup of diesel fuel per hour as opposed to at least a half-gallon of fuel per hour of idling. Block engine pre-heaters cost approximately $1200 - $1500, installed. Some of the reported benefits of these heaters are lower emissions and fuel savings, less wear-and-tear on the engine, and relatively easy installation and maintenance. They can be used in remote yards or other situations where electrical block heaters are not practical or available to install and can be started by a timer, potentially saving time that would have been used to start and idle the buses. (EPA 2012)
  • Compartment/Engine Block Heaters warm up the engine block and passenger compartments simultaneously while using an auxiliary heater. These heaters cost approximately $2300 - $2500 installed. The heaters use only one cup of fuel instead of the half-gallon of fuel needed to idle for an hour. These heaters are especially useful for nighttime-activity buses and buses that transport very young and/or special-needs children. In addition, the radiant heat keeps the windows from frosting or fogging, which is an added safety benefit (EPA 2012).
  • Electric Plug-in Block Heaters allow engines to have a “warm start” on cold days without additional idling. These heaters warm up a vehicle’s engine block by heating the engine coolant or oil. This type of heater is mounted on the engine block of each bus and is plugged in when the bus is parked at the depot. Bus depots and garages can be designed or retrofitted to bring in the electrical service required. Such heaters usually cost less than $100 (EPA 2012).

Diesel Fuel Emissions

Michigan Policy Highlights

  • No Michigan state policy met our specific criteria to address diesel emissions.
  • The Michigan Clean Diesel Initiative (MiCDL) is a coalition of government, industry, and non-profit organizations which meets 3-4 times per year in order to address diesel pollution issues in the state. While the MiCDL acts as a conduit to help organizations identify funding opportunities, direct funding from the state of Michigan for diesel emissions reduction programs is minimal.

Analysis and Policy Highlights from Other States

  • The federal government has taken several steps to reduce pollution from diesel-fueled vehicles:
  • In 2006, the federal government promulgated regulations to require clean “ultra-low sulfur” diesel fuel (a sulfur level at or below 15 parts per million [ppm]) for highway diesel engines. Beginning in 2007, “low sulfur” (below 500 ppm) diesel fuel was required for non-road diesel engines, and “ultra-low sulfur” fuel was required by 2010. Locomotives and marine engines are required to use ultra-low sulfur fuel by 2012 (EPA 2007b).
  • The federal guidelines affect model year 2007 and later “heavy-duty engines,” cap particulate matter at 0.01 grams per brake horsepower-hour (g/bhp-hr) and phase in lower NOx and non-methane hydrocarbons (NMHC) standards (EPA 2001). The federal standards equal the California emissions standards that have been in effect since 2004.
  • The federal government also issued standards to reduce emissions (using technology like particulate traps) from the highway fleet beginning in 2007 and from the non-road sector beginning in 2011 (EPA 2007b).
  • Several states have enacted additional legislation or regulations to further reduce diesel pollution. This is a selection of these efforts:
  • California has long been ahead of national standards in its diesel emissions requirements, instituting a cap on particulate matter emissions of 0.01 g/bhp-hr beginning with model year 2004 “heavy-duty diesel-fuel, dual fuel, and bi-fuel urban bus engine[s],” three years before the federal standards went into effect.
  • Several states have implemented vehicle emission testing:
  • The Iowa Department of Natural Resources has instituted the Bus Emissions Education Program (BEEP) that voluntarily tests buses for emissions.
  • The Massachusetts Department of Environmental Protection requires heavy-duty diesel vehicles to undergo emissions testing every two years, and requires remediation (within 60 days) if a vehicle fails testing (310 CMR 60.02). Furthermore, all new school buses (model year 2005 and later) used in Massachusetts must meet California emissions requirements.
  • New Mexico requires that 75% of vehicles purchased by government agencies and educational facilities are "capable of operating on alternative fuel or are gas-electric hybrid vehicles," which would have fewer emissions (N.M. Stat. Ann. § 13-1B-3).
  • New York’s Diesel Emissions Reduction Act of 2006 requires that a yearly list of diesel-fueled vehicles owned and operated by state agencies; the list includes which vehicles are using the best-available retrofits for diesel emissions reductions.

Evaluation and Recommendations

Diesel emissions regulation has been led by the federal government; but, a growing number of states have taken steps to reduce toxic diesel emissions, including California which has been in the forefront of policy activity to better protect children. Michigan should consider taking the lead on policies that reduce diesel emissions to improve air quality and public health. Furthermore, Michigan should seriously consider implementing a statewide policy for retrofitting existing state and municipal vehicles in order to reduce exposure to diesel emissions. This policy should include funding for state and municipal organizations to retrofit their vehicles and tax credits for private organizations to do so.

Policies on School Bus Pollution

Michigan Policy Highlights

No Michigan policy has met our specific criteria to address school bus pollution.

Analysis and Policy Highlights from Other States

  • Many states have implemented programs to reduce diesel emissions from school buses, and the federal Environmental Protection Agency has implemented the “Clean School Bus Grant Program,” using $7 million dollars appropriated by Congress. The program provides grants to school districts to retrofit their existing school bus fleets or to assist in the purchasing of new buses that have far lower diesel emissions.
  • Several other states have implemented legislation or regulations that limit the time allowed for school bus idling and/or require a minimum distance for the parking of buses near school buildings.
  • The California Air Resources Board issued airborne toxic control measures regarding school bus idling. These measures require bus drivers to turn off engines when arriving at, and within 100 feet of, school zones and to not restart more than 30 seconds before leaving––therefore preventing idling for more than 5 minutes outside of school zones.
  • Connecticut makes it a finable infraction to leave a school bus idling for more than three consecutive minutes (Conn. Gen. Stat. § 14-277).
  • The Maine Department of Environmental Protection, Bureau of Environmental Quality instituted the Maine Clean School Bus Program that supports limiting idling, retrofitting buses to decrease emissions, and other voluntary advocacy measures.
  • Minnesota requires operators of school buses to "minimize, to the extent practical, the idling of school bus engines and exposure of children to diesel exhaust fumes" and requires the parking of school buses "at sufficient distance" from school air-intake systems, when practicable (Minn. Stat. § 123B.885).
  • Many states have implemented retrofit programs for school buses:
  • The California Air Resources Board (CARB) has implemented a Lower-Emission School Bus Program, which provides grants to school districts to purchase new school buses (which are emissions-free or emit significantly fewer emissions than current buses) or to place air pollution control devices on existing buses (CARB 2006). The program has placed controls on 10% of California’s buses, and has caused an estimated 8.7% reduction in soot produced by school buses (UCS 2006). The program had been paid for via legislative appropriations, the Transportation and Air Quality Bond (Proposition 1B, passed in 2006), provides $200 million for retrofitting and purchasing new buses (California Air Resources Board).
  • Arkansas authorizes the Division of Public School Academic Facilities and Transportation to develop and implement "Reasonable life-cycle replacement policies" to bring about emissions improvements into school bus fleets (A.C.A. § 6-19-122).
  • California places a surcharge on motor vehicle fees, with funds from one of the surcharges to be used, in part, to fund the purchase of school buses in the "Lower-Emission School Bus Program" (Cal Health & Saf Code § 41081).
  • Connecticut requires each school bus with a engine model year of 1994 or later to reduce its diesel emissions by September 1, 2010, by either installing a "closed crankcase filtration system," and a level 1, 2, or 3 device, depending on the model year; having an engine that meets EPA 2007 emissions standards; or having an engine that uses compressed natural gas (or another fuel certified by the EPA or California Air Resources Board that reduces particulate matter emissions by at least 85% compared to ultra-low sulfur diesel fuel). The act authorizes the Department of Administrative Services to enter into procurement contracts to purchase crankcase and level 1, 2, and 3 devices (Public Act 07-04, Section 17).
  • Connecticut created a "school bus emissions reduction account" to fund the "school bus emissions reduction program." The program, established by the state Environmental Protection Agency and the Department of Education, is authorized to make grants to municipalities and school boards to (1) reimburse them for the costs of retrofitting buses to make them compliant with school bus emissions requirements, (2) develop a program for educating and notifying municipalities of the new school bus emission requirements, and (3) assist municipalities and school boards with retrofitting their busses and giving them guidance into how to do so (Public Act 07-04, Sections 18-19).
  • The Maine Department of Environmental Protection, Bureau of Environmental Quality instituted the Maine Clean School Bus Program, which supports efforts such as the retrofitting of buses to decrease emissions.
  • New Jersey requires the Division of Motor Vehicles to institute a "school bus enhanced safety inspection program," which must include standards regarding diesel emission inspections to ensure that buses meet the state's emission standards (N.J. Stat. § 39:3B-21).
  • New Jersey requires the DEP to ensure the retrofitting of all diesel vehicles in the state with the best available technology to reduce particulate emissions from diesel engines (N.J.S.A. 26:2C-8.26).
  • New York established the "Clean-Fueled Buses Program," to permit municipalities or school districts to apply to the New York state energy research and development authority for funding to purchase clean-fueled buses and/or retrofit equipment for diesel-fuel school buses, and for assistance with infrastructure to make buses cleaner (NY CLS ECL § 56-0605).
  • The Ohio EPA has a Clean Diesel School Bus Fund through which grants for retrofit projects are awarded. Since its inception in 2006 the program has awarded over $7.5 million dollars to retrofit over 1,000 school buses. The program is funded by fines levied against individuals and organizations that violate environmental regulations (Ohio EPA, 2012).
  • The Oregon legislature passed HB2172 to encourage schools to replace or retrofit buses by exempting funds used for those purposes from school transportation grant funds.
  • Rhode Island banned the use of school buses with model year 1993 engines (and older ones) by September 1, 2010. The bill also requires by September 1, 2010 (provided that there are sufficient federal or state funds) that newer buses either (1) be retrofitted with a crankcase ventilation system and a level 1, 2, or 3 device; (2) have a model year 2007 or later engine; or (3) achieve diesel PM reductions through the use of alternative fuels, such as compressed natural gas, that reduce DPM emissions (R.I. Gen. Laws § 31-47.3-3).
  • Rhode Island mandates that childcare and school extra-curricular vehicles be inspected for excessive emissions (HB 6371, 2007), and also mandates that “pupil transport vehicles" (vehicles used by schools to transport fewer than 8 students) be inspected for excessive emissions (SB 556, 2007).
  • Texas established a "Clean School Bus Program" to lessen children's exposure to diesel exhaust. The program can fund: diesel oxidation catalysts for buses built before 1994, particulate filters for buses built from 1994 to 1998, the purchase of emissions-reducing add-on equipment, the use of qualifying fuel, and other technology that the Texas Commission on Environmental Quality determines will reduce emissions (Tex. Health & Safety Code § 390.002). Any Texas school district that has diesel-fueled school buses can apply for grants (Tex. Health & Safety Code § 390.003). The program was scheduled to sunset in 2013, although as of 2011 there are no grant funds eligible for the program (Tex. Health & Safety Code § 390.006).
  • Washington State statute requires 85% of funds in the Air Pollution Control Account (which receives a statutory 85% of 58.12% from car ownership certificate fees) to be used for the retrofitting of school buses with “exhaust emission control devices” or to provide funding for necessary “fueling infrastructure” to permit school bus fleets to use alternative, lower emission fuels (Rev. Code Wash. (ARCW) § 70.94.017). Thirty-eight percent of Washington’s bus fleet was retrofitted with “diesel oxidation catalysts” by 2005, resulting in a 7.3% decrease in soot produced by school buses (UCS 2006).
  • Prior to model year 2007, diesel emissions requirements in California were more stringent than those implemented by the federal government. Massachusetts implemented tougher emissions standards in 2005, prior to the implementation of stricter federal standards.

Evaluation and Recommendations

To lower diesel emissions, Michigan should strongly continue applying for federal grants and consider appropriating state funds for the replacement and retrofitting of diesel emitting school buses. Additionally, Michigan should strongly consider legislation to regulate school bus idling by limiting allowable idling time and requiring school buses to park at a sufficient distance from schools.

Diesel Truck and Commercial Vehicle Idling

Michigan Policy Highlights

  • No Michigan state policy met our specific criteria to address diesel truck and commercial vehicle idling.
  • The city of Detroit has an idling ordinance which prohibits idling of diesel and non-diesel vehicles weighing over 8,500 lbs for more than 5 minutes, with limited exceptions (Detroit Ord. No. 04-10, § 1, 3-8-10 Sec. 55-6-91 – Sec. 55-6-95).
  • Mt. Clemens also has a similar idling ordinance (Mt Clemens Ord. No. 32.400, 9-3-04).
  • State Senator Ray Basham (D) introduced Senate Bill 1069, a proposed ban on unnecessary commercial diesel vehicle idling, in January 2010; however, the bill was stalled in the Senate Transportation Committee and never came to a vote. This bill made no exemptions for ambient air temperatures below freezing, but did make an exemption for the usage of auxiliary power units running on diesel fuel.

Analysis and Policy Highlights from Other States

  • A number of other states, and many municipalities, have implemented legislation or regulations that limit the idling time allowed for diesel-fueled commercial and public vehicles.
  • California bans diesel-fueled commercial motor vehicles (weighing >10,000 pounds) from idling for more than 5 minutes, with limited exceptions (Rule 2485 of Chapter 10 - Mobile Source Operational Controls, Article 1 - Motor Vehicles, Division 3. Air Resources Board, title 13).
  • Delaware mandates that "on-road heavy-duty motor vehicle[s],” defined as, vehicles weighing more than 8,500 pounds, not idle for more than 3 minutes. However, this legislation specifically exempts school buses while students are on board (DNREC Rules Title 7.1100.1145).
  • Washington, D.C. bans the idling for more than 3 minutes of any "diesel powered motor vehicle," including buses for more than 12 passengers, with very limited exceptions (DC Municipal Regulations Title 20 Sec. 900.1).
  • Hawaii bans the idling of vehicles in any "off street area" with some exceptions (Hawaii Administrative Rules §11-60.1-34(c)).
  • Maryland prevents vehicles from idling for more than 5 minutes, with limited exceptions (Md. Transportation Code Ann. § 22-402(c)(3)).
  • Massachusetts bans "the unnecessary operation" of an engine if the vehicle is stopped for more than 5 minutes (M.G.L. Chapter 90, Section 16A & 310 CMR 7.11(1)(b)).
  • Nevada bans the idling of a diesel truck or bus for more than 15 consecutive minutes unless a variance is issued, emissions are contained in an approved manner, or other exceptions are met (Nevada Administrative Code 445B.576(4)).
  • New Jersey Department of Environmental Protection regulations prohibit diesel-powered vehicles from idling for more than three consecutive minutes (N.J.A.C. 7:27-14).
  • New Hampshire limits idling of “diesel-powered motor vehicle[s],” depending on temperature (i.e. to 5 minutes if the temperature is above 32F, 15 minutes if it’s -10F to 32F, and no restrictions if it’s below -10F), with some exceptions (New Hampshire Department of Environmental Services, Air Resources Division Rules Env-A 1101.05).
  • New York bans the idling of a "heavy duty vehicle” powered “by a diesel or non-diesel fueled engine" for more than 5 consecutive minutes, with some exceptions (New York Code of Rules & Regulations 6:3-217-3.2).
  • Rhode Island bans the “unnecessary operation” of a diesel motor vehicle engine for more than 5 minutes in a 60-minute period (R.I. Gen. Laws § 23-23-29.2).
  • Illinois and Arizona mandate that certain counties and townships of the state limit idling, while Texas bans idling by diesel trucks in the state from April 1 - October 31 (625 ILCS 5/11-1429, A.R.S. § 11-876, TAC Title 30 RULE §114.512).
  • The Environmental Protection Agency released a “Model State Idling Law,” which advises states to limit idling by commercial diesel-powered vehicles to 30 minutes during loading and unloading times and to 5 minutes per hour at all other times (EPA 2006b).

Evaluation and Recommendations

  1. Michigan should eliminate all non-essential idling.
    1. Idling shall be limited to 5 minutes out of any 60 minute period UNLESS:
      1. 30 minute idle limit per hour during loading and unloading times (ex. while waiting to unload). This does not apply to school buses, which should abide by the 5-minute idle limit during loading and unloading times.
      2. Exceptions: traffic, health or safety, emergency vehicle, maintenance/testing, armored vehicle, if the idling is required for work-related mechanical or electrical operations (ex. mixing, cargo processing)etc. (Detroit Ord. No. 04-10, § 1, 3-8-10 Sec. 55-6-93)
      3. The vehicle is using a smaller, diesel-fueled auxiliary power unit to power or heat the cabin.
    2. Truck stops with 25 or more spaces must install truck stop electrification (TSE) facilities for 80% of spaces; allowing heating and appliance usage in diesel trucks without the need for engine idling.
    3. The DNRE shall conduct an analysis for locomotive and marine idling.
    4. The DNRE shall develop a plan to educate state, municipal, and commercial, operators and owners on the benefits of idle reductions and train law enforcement agencies to enforce idling limitation laws.
  2. Michigan should require clean construction specifications for public works contracts.
    1. ANY public works contract with a public agency must:
  1. Must install closed crankcase vents (CCV) or similar technology to keep diesel pollution from being vented into vehicle cabins.
  2. No non-essential idling
  3. Any non-road vehicle on site (not generators) for more than 3 days must have installed control technologies (Level 1 by 1/1/14, Level 2 (25-75 horsepower) by 7/1/17, and Level 3 for 75+ horsepower by 7/1/17. Levels correspond to California Air Resources Board levels described above.
  4. All heavy duty (over 14,000 lbs) diesel vehicles and generators must have Level 1 controls by 1/1/14 and Level 3 by 7/1/14
  5. Require compliance sticker, proper maintenance, etc.
  1. The contract reimburses (full or partial – amount determined by agency) for cost of coming into compliance.
    1. May provide one time only reimbursement (can be via rebates)
    2. Does not apply to compliance with other state or federal laws
    3. Costs are not included in the bid so are not considered
  1. Michigan should require fleet owners and operators to install the strongest possible (Level 3) emission control technology on ALL “regulated highway vehicles” (buses, garbage trucks, cargo trucks with central fleet maintenance or fueling in MI, etc.)
    1. At least 50% of fleet within 2 years after implementation.
    2. 100% of fleet within 3 years after implementation.
      1. Extra time to comply if:
        1. Already have controls but they are not the strongest possible (Level 2= + 4 years, Level 1= +2 years)
        2. Small fleet (5 or less)= +2 years
      2. Can use lesser control (Level 2 or Level 1) if the Department of Natural Resources and Environment (DNRE) finds that Level 3 controls will not work with the vehicle.
      3. Excludes vehicles that operated less than 100 hours and for fewer than 1,000 miles in Michigan. (Requires verification.)
    3. Must install closed crankcase vents (CCV) or similar technology to keep diesel pollution from being vented into vehicle cabins.
    4. Includes hefty sanctions ($5,000 per violation and possible revocation of vehicle registration.).
    5. After 7/1/13 any vehicle without controls that is +25 years old must rebuild the engine.
  2. Michigan should reduce non-road diesel emissions by:
    1. Requiring the DNRE to adopt California Air Board (CARB) rules for non-road diesel vehicles to reduce particulate matter (PM)
    2. After 1/1/15 public agencies may lose state funding if they have not installed Level 3 (or best possible) controls on any vehicle owned, operated, or leased by that agency. May also be able to get additional funding if comply earlier.
  3. Michigan should create a single inventory of state/municipal diesel vehicles, which should document make, model, year, and any retrofitting upgrades.
  4. Michigan should create a Diesel Emissions Reductions Fund (DERF)—Treasurer may accept funds from the following sources but list is not exhaustive (2% max to be used to administer fund):
    1. 1% surcharge on lease or rental of non road diesel vehicles
    2. 2.5% surcharge on lease or rental of heavy-duty vehicles 2006 and older
    3. Percentage of the tax on diesel fuel
    4. Registrations of diesel boats
    5. Bonds
  5. Michigan should identify fine particulate emission hot-spots around the State which will be defined as locations where diesel particulate matter emissions and fine particulate matter concentrations are at their highest concentrations levels and implement action plans to reduce emissions in these communities.
  6. Michigan should require that a freight facility shall not commence significant expansion (over 10 tons of PM2.5/year) without permit. In order to get a permit:
    1. Must do a baseline study of the annual particulate matter (PM) emissions from all sources servicing the facility
    2. Inventory of PM pollution for each of the next 5 years after facility completed
    3. Plan to reduce emissions and opportunity for public comment, and regular reporting compliance with plan
  7. Sanctions for non-compliance
  8. Michigan should allow bonding for revolving loan programs for truck stop electrification and other diesel reduction projects.
  9. Michigan should create a Diesel Emission Reduction funding program (DERF). Financing for emission reduction may come in the form of grants, rebates, or low-interest revolving loans on a competitive basis to achieve significant PM reductions.
    1. The DNRE would manage this program, create criteria, monitor for achieving reductions.
    2. Grants—
      1. Prioritization to:
        1. Fleets owned and operated by public agencies
        2. Remaining funds (if any) to private vehicles benefitting public agency
        3. If funds remain, then to private fleets for private business
      2. Application must include: description of air quality, measure proposed, evaluate benefits using DNRE criteria, cost, expected lifetime, fuel available, monitoring/verification.
      3. Eligible projects: retrofits, repowering new engines, CCV, idling reduction equipment. Truck stop electrification eligible for loans but not grants. Also, must be for project that is at least 75% in Michigan.
      4. Criteria:
        1. maximize public health benefits;
        2. serves areas that: have the highest population density, poor air quality, disproportionate quantity of diesel pollution, and use collaborative process;
        3. maximize useful life of technology;
        4. conserve diesel fuel;
        5. Emissions reductions of at least 50% (unless DNRE decides more beneficial to use different number.)
        6. Meet cost-effectiveness requirements: not more than $135,000/ton of PM10 emissions, no grant more than the cost of the proposed measure (+tax, -credits/rebates), DNRE discretion to change cap.
    3. Rebates—
      1. The DNRE shall set-up a system to issue rebates, reserve rebates, first-come first-serve, not (with exceptions) to be used for emissions reductions trading, report on funding program.
  10. Michigan should create diesel smoke opacity standards
    1. Smoke from diesel vehicle cannot exceed opacity of:
      1. 40% (before 1990)
      2. 30 % (’90-’96)
      3. 20% (after ’96)
    2. The DNRE may allow exemptions if engine type cannot meet standard.
    3. The DNRE/MDOT will create an inspection program (both regular--at least once a year-- and random inspections), charge fees, and collect fines.
  11. Michigan should require the DNRE to implement diesel emission reduction programs, including:
    1. reporting requirement (including public notice/comment),
    2. fleet reporting requirements, and
    3. DNRE promulgation of rules.


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