When it comes to the potential hazards of diesel exhaust, Randy Dunn, an owner-operator for Universal Am-Can, is unconcerned.
“Sometimes I have gotten out of the bunk with a headache from an exhaust leak, but the old timers say that’s about all it will do to you,” he says. “It won’t kill you.”
The old-timers are wrong. Though it takes a concentrated dose of carbon monoxide to kill you, prolonged exposure to small amounts can cause much more than headaches. Burning eyes, dizziness, labored breathing, chest pains, nausea, stiff joints, sleep disorders, and visual and mental impairment are among the symptoms attributed to poisoning from CO or certain other components of diesel exhaust.
Dunn, because he has always run older trucks, faces an above-average risk. Though it’s rare for deadly CO to leak into a truck cab, it can happen, especially as equipment ages. Furthermore, engines produced before October 2002 did not have to meet emissions standards as strict as today’s.
Experts differ on the degree of risk the average trucker faces by working around diesel exhaust. Much of this difference is due to insufficient or inconclusive testing of air quality at truck stops, say University of Minnesota air quality specialists. A Health Effects Institute study quoted on DieselNet.com notes that “information on ambient exposure [to diesel exhaust] is sparse.” Bill Fay, president of the National Association of Truck Stop Operators, says he would like to know if any studies point to such a problem. “The health of our employees and customers is a real concern to us,” Fay says.
Some experts compare the risk of exposure to diesel exhaust to that of getting lung cancer from second-hand cigarette smoke. Plenty of industry veterans, especially those who like to keep the ancient iron up to snuff, feel the same way. Dennis Steffler a 31-year over-the-road veteran who is now a Snap-On dealer, smiles when he remembers the old Detroit Diesel 318s and Big Cam Cummins, both noted for their smoke at start-up and when pulling a big load up a long hill.
“The old mechanicals would smoke until the turbo caught up with the fuel in the cylinder and gave it some air, especially when they were cold,” Steffler says. “Some guys would disable the aneroid or put a vise grip on the return line from the pump to get more fuel pressure. That made even more smoke.”
The advent of electronic engines put an end to such tricks and the black plumes that often accompanied them. Mandates from the U.S. Environmental Protection Agency continue to purify diesel emissions. The October 2002 deadline required heavy-duty diesel engines to emit no more than 2.5 grams of nitrous oxide and non-methane hydrocarbons, a reduction of nearly 90 percent from previous levels. The 2007 emissions requirements, aided by low-sulfur diesel standards beginning in 2006, will make diesel exhaust much cleaner.
Even with these improvements, no one is suggesting that you take deep drafts of exhaust into your lungs or continue to work in a cab you know to have exhaust leaking into it. Furthermore, you can protect yourself by following these practices:
- Consider generators or opti-idle technology to run air conditioning and heat. This will allow you to keep vents and windows closed.
- Be aware of weather conditions. Ozone, which is hazardous, forms on hot, sunny days when exhaust reacts with sunlight and tends to settle near the ground. Lack of a breeze allows ozone to hang in the air as night falls. Ozone is less likely to form in cold or cloudy conditions.