Environmental Impact of Diesel Engines in Transportation Vehicles/Off-Road Engines


            Diesel engines are utilized in both common and uncommon transport.  They play a major role in the American economy, but also prove to be a very dangerous source of pollution.  An off-road vehicle is just what it sounds like, a vehicle that does not travel by road such as the common car.  The type of transportation included in this is comprised of locomotives, agricultural equipment such as tractors, construction and mining equipment like graders and back hoes, and also marine vessels.  Off-road diesel engines are much like their counterparts that are used in normal passenger vehicles, except that they don’t have the emission controls that are commonplace in on-road cars.  In both on-road and off-road transport, diesel engines can be found nationwide, and their effects on the environment can be identified easily.



Environmental Impact of Diesel Engines in Transportation Vehicles

Diesel exhaust contains fine particulate matter, and diesel engines are one of the largest sources of these particles.  These can be a serious health problem as they can easily become lodged in the lungs, thus causing lung damage and potentially death.  Also, they can provoke already prevalent respiratory conditions, especially bronchitis and asthma.  The exhaust from diesel engines can also cause cancer in human beings.  It is estimated that fine particulate matter, many of which coming from the exhaust of diesel engines, causes about 15,000 premature deaths yearly in the United States.  People with already existing health problems such as asthma, as well as most children, are most at risk from fine particulate matter.  Not only is diesel exhaust from on-road vehicles damaging to one’s health, it also contributes to haze, acid rain, ozone formation, and climate change globally.  There are things that owners of diesel engine on-road vehicles do, including:

The diesel engines used in the common car are considered very efficient compared to gasoline engines.  In this way, it may be more economic to choose a car with a diesel engine, as you will get farther on what you have.  While many consider diesel engines to be a dirty variety as their emissions are far more polluting than those of the gasoline engine, changes are underway.  The U.S. has made adjustments in 2006 that have employed the usage of diesel fuel with ultra-low sulfur content.  This will help to eliminate much of the irritating exhaust fumes you used to get from diesel engines.  Thus, the diesel engine in transportation vehicles could soon be legitimately more preferable than the gasoline engine many are accustomed to.  This ultra-low sulfur diesel that is being forced upon American engines will prevent incredible amounts of pollution as it is phased into usage, and will lower the sulfur content in highway diesel fuel from 500 parts per million to 15 parts per million.  Once this change in policy has been completed, the following changes will have been made:



Environmental Impact of Diesel Engines in Off-road Transport

            Currently, diesel-powered engines remain one of the most dangerous sources of air pollution.  This is also the case with the off-road transportation that uses diesel engines, with an example being that commercial ships in the United States emit about 1,000,000 tons of smog-forming nitrogen oxides yearly, the same amount that you would need millions of cars in order to produce. As said before, these sources include locomotives, construction and mining equipment, agricultural equipment, and commercial marine ships.  As a group, off-road engines discharge more fine particulate sooty matter than any other source of transportation.  This group lacks the advanced emission controls seen in on-road vehicles, and thus has been poorly controlled up until this point.  Since 1980, annual nitrogen oxide discharges have increased 25% from off-road engines, making up a significant portion of all United States emissions of nitrogen oxide.  Similar to on-road vehicles, off-road diesel engines are also helping to contribute to acid rain, reduced visibility as a result of haze, and the corrosion of estuaries.  Nonroad engines can also be given some of the responsibility for the asthma attacks that soot and smog can provoke, and the increased risk of lung cancer that comes from this carcinogenic particulate sooty matter.  Lastly, diesel engines are also responsible for great amounts of nationwide sulfur dioxide pollution, brown clouds over urban areas and haze in national parks. 

The government has taken an active role in this problem, and has produced some new regulations that will attempt to reduce the toxic emissions of some off-road sources such as bulldozers and tractors.  The lower-sulfur diesel fuel mentioned earlier is being put into use in certain off-road vehicles as well, and can help to reduce particulate matter pollution by more than 90%.  These new rules are going to be phased in by 2008 and put into full-scale use by 2015.  As a result, sulfur content will be slashed by 99% by 2010, and commercial shipping and locomotives will be required to follow these guidelines as well by 2012.  Diesel machines classified as off-road will be subjected to stricter guidelines including those used in mining, agriculture, construction, and industrial work.

New programs were also announced that plan to tighten emission standards for commercial ships and locomotives, and would apply to new marine diesel engines and both new and re-manufactured diesel locomotives. Although locomotives and marine commercial vessels that run on diesel are placed in the broad category of off-road diesel vehicles, the EPA has separate regulations for each. Ultimately, the Environmental Protection Agency estimates that by 2030, the changes that are being made now will prevent about 12,000 premature deaths, 6,000 asthma related ER visits, 9,000 hospitalizations, 15,000 heart attacks, and 1,000,000 missed work days each year.  With changes expected as drastic as these, there is a justified hope for a cleaner and safer future.         







(2006). Diesel Nonroad Engines. Retrieved November 29, 2006, from Environmental Defense Web site: http://www.environmentaldefense.org/subissue.cfm?subissue=12


What kind of car?. Retrieved December 3, 2006, from Institute for Lifecycle Environmental Assessment Web site: http://www.ilea.org/articles/car.html


(2006). Heavy-duty highway diesel program. Retrieved December 3, 2006, from U.S. Environmental Protection Agency Web site: http://www.epa.gov/otaq/highway-diesel/index.htm


(2006). Diesel exhaust in the United States fact sheet. Retrieved December 3, 2006, from U.S. Environmental Protection Agency Web site: http://www.epa.gov/otaq/highway-diesel/basicinfo.htm