Why don light-duty, diesel-powered vehicles have to get a Smog Check?
Inclusion of light-duty, diesel-fueled vehicles was considered during development of the Smog Check Program. It was determined that when compared to the nation’s vehicle fleet as a whole, light-duty, diesel-fueled vehicles and trucks represent a small portion of the entire fleet, less than one percent. In addition, while particulates are visible in diesel exhaust, smog-causing carbon monoxide and hydrocarbon emissions from diesel-fueled vehicles are comparatively low. Testing for NOx (oxides of nitrogen) in diesel emissions is under evaluation. With light-duty diesel vehicles comprising less than one percent of the total number of California registered vehicles, the costs associated with implementing a new regulatory program to include these vehicles are currently prohibitive.
Related Questions
- I see that 30% of my light-duty vehicles that are "new to the fleet" must be clean fuel vehicles in model year 1999. What does "new to the fleet" mean?
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- Why don light-duty, diesel-powered vehicles have to get a Smog Check?
