December 22, 2006—For the first time, the US Environmental Protection Agency (EPA) is proposing that emissions control systems of large diesel and gasoline highway trucks and buses must be monitored similarly to passenger cars.
EPA’s proposed regulation for onboard diagnostic (OBD) systems for large trucks and buses would help ensure that emissions control systems work properly for the useful life of heavy-duty on-road vehicles, says the agency.
Onboard diagnostic systems, used in passenger vehicles since the mid-1990s, monitor emissions control components, detect need for emission-related repairs, and alert the vehicle’s operator of these problems. They also help inform service technicians what problem exists so that it can be repaired properly. The OBD systems for highway trucks will work the same way, explains EPA.
The proposed requirements are part of the Clean Diesel Truck and Bus Program, which will reportedly result in significant reductions of nitrogen oxides, particulate matter, non-methane hydrocarbons, carbon monoxide, sulfur dioxide, and air toxics from diesel-powered vehicles.
For more information on the EPA action, visit EPA’s Heavy Duty Vehicles page.
