Diesel exhaust carefully regulated

This letter is in response to the opinion of Mr. J. Arneberg whose letter, published on Aug. 11, complained about diesel trucks and "the black, carcinogenic bile that these vehicles belch into our air."

He further states that diesel exhaust is "lightly regulated" and further asks: "Why are we not regulating diesel fuel?"

In response, I wish to explain that emissions from on-road diesel engines have been regulated since 1974 and that a great deal of work has been done by voluntary consensus to improve diesel engine fuels since the 1980s.

Specifically, in 1974, diesel engine exhaust limits were first established for engines built in that year. These were reduced in 1987 and again in 2015.

Furthermore, smoke opacity limits have been imposed for the most stringent operating conditions since 1974. To meet these requirements, engine manufacturers have had to develop new technologies including particulate traps, computer controlled fuel injection and special techniques to control nitrogen oxides formed in fuel combustion.

Furthermore, limits for sulfur in diesel fuel have been tightened from 5000 parts per million (ppm) to 500 ppm to 15 ppm to accommodate the various vehicles on the road.

Engine manufacturers are also taking advantage of other fuel-related technologies such as renewable biodiesel and operating diesel engines on natural gas.

Similarly, there has been a parallel effort to reduce engine emissions for off-road diesel vehicles as well.

Charles E. Glomski

Elk Grove Village