Diesel Exhaust: Controlling Exposures

The best option for preventing exposure to diesel exhaust is to prevent it from being generated. This can be accomplished through several different means. First diesel engines can be replaced with engines that use alternative fuels such as liquid propane or compressed natural gas. Second, diesel fuels can be reformulated to reduce the amount of sulfur and other contaminant generating compounds that they contain. Third, diesel engines can be redesigned to reduce the amount of pollutants that they generate. Finally, emissions control equipment can be added to existing diesel engines. These engines emit far fewer pollutants than diesel engines, particularly diesel exhaust.
http://www.nrdc.org/air/transportation/fdiesel.asp
http://www.greendieseltechnology.com/welcome.html
http://www.trucks.doe.gov/plain-talk/diesel_faq.html

Diesel fuel reformulation can be a relatively simple and straightforward process. The reformulation most commonly used today and required by the EPA for On Road diesel engines in 2007 is to reduce the sulfur content of diesel fuel from as high as 3000 ppm to less than 15 ppm. Another option is to use biodiesel, which can be generated from many types of vegetable oil and tallow. The oil that is used can be virgin or it can be recovered from restaurant greases. Diesel engines currently in use can use biodiesel blended with some proportion of diesel or they can use 100% biodiesel.
http://ecdiesel.com/decade.html
http://www.biodiesel.org
http://www.ott.doe.gov/biofuels/

Diesel fuel reformulation may allow better emissions control technology such as particulate traps and catalytic converters to be used. The particulate traps can remove up to 95% of the particulates that are present in diesel exhaust. Traps that have a catalytic action can remove up to 90% of carbon monoxide, 90% of hydrocarbons, and 10% of nitrogen oxides present in diesel exhaust. Oxidation catalysts can be used light in light trucks and cars in addition to heavy duty vehicles. These catalysts are able to remove up to 90% of carbon monoxide, 90% of hydrocarbons, and 25-50% of particulate matter in diesel exhausts. http://www.cleanup.org.uk/cleanup_techno.html

Control of Occupational Exposures

People are exposed to diesel exhaust in occupational and nonoccupational environments. It is possible to control the exposure of workers to diesel exhaust. However, it is difficult or impossible to control exposure to diesel exhaust in nonoccupational settings because it is released into the environment and is widespread. Nonoccupational exposures to diesel exhaust can be minimized by having drivers turn off the engines while they are waiting to pick up passengers or making deliveries at a building.

Occupational exposures to diesel exhaust can be controlled in four ways. First, when diesel engines are being worked on in a workshop their tailpipes can be connected to local exhaust ventilation equipment that vents the exhaust to the outdoors. Second, general ventilation, fans or ventilation that serves the whole workshop can be used to dilute the diesel exhaust and to minimize its buildup within a workshop. Third, the cabs or cabins of vehicles with diesel engines can be provided with filtered air and or air conditioning to prevent diesel exhaust from entering the cabin. For this to be successful, cracks and leaks in the cabin should be sealed. The least desirable option is for operators of diesel-powered equipment to wear respirators that filter out oily particulates and organic compounds while operating the equipment. http://www.hse.gov.uk/pubns/indg286.htm