Dear Street Smarts,
Occasionally, I see idling vehicles on West Cliff Drive while folks read a magazine, take a nap, or to get out to take pictures of the beautiful views. Neighbors have vehicles idling in their driveway or on the street for five minutes or more while waiting for someone to emerge from the house. In the parking lot at grocery stores or at the mall, folks are sitting in their car with the engine running for no apparent reason. Trucks sit idling for extended periods while loading or off loading stuff. It seems to me that if you were idling your vehicle for more than a minute or two it was better to shut off the engine to save fuel and minimize exhaust. What can you tell us about this? Hybrids or electric cars wouldn't matter? Does it depend on gas vs. diesel? Can you cause damage to the engine by turning it off and on too frequently? Thank you for your help to educate us about such an unconscious and pervasive thing.
Ron Pomerantz via email
California Air Resources Board rules limit the idling of large diesel trucks and school buses, said David Frisbey, Air Quality Planner for the Monterey Bay Unified Air Pollution Control District.
"Generally speaking, large diesel commercial trucks and school and transit buses are prohibited from idling within 100 feet of a school," he said. "In other locations, idling is limited to no more than five minutes. Neither the air district nor the air resources board have specific limits on idling passenger vehicles."
All vehicles, including trains, with heavy smoke chugging out of their tailpipes should be reported to the air board at 1-800-END-SMOG or
, Frisbey added.
Note, though, that hospitals tend to have no idling signs posted at drop off areas.
Another factoid: Car engines emit more pollutants after cold starts because their engines aren't burning fuel efficiently and the catalytic converter isn't at a high enough temperature to operate effectively. While noting that pollutants hover nearby cars after cold starts, he recommended that drivers begin to drive soon after starting their vehicle to allow the pollutants to dilute.
Learn more at http://arb.ca.gov/toxics/sbidling/sbidling.htm
Meanwhile, Jeanne LePage of Ecology Action suggested taking a gander at the websites of the Environmental Defense Fund, http://www.edf.org/transportation/reports/idling
, and the Environmental Protection Agency, http://www.epa.gov/cleanschoolbus/antiidling.htm
Here are some highlights:
- Diesel exhaust contains more than 40 air pollutants in the form of fine particulate matter that is so small, several thousand could fit on the period at the end of this sentence. Thus, they are small enough to enter the nose and throat, getting lodged in the lungs and causing damage, chronic respiratory illness -- such as lung disease, asthma and bronchitis -- and premature death.
- Children are most at risk because their respiratory systems are still developing and they breathe at a faster rate than healthy adults.
- Idling creates unnecessary wear and tear on vehicle engines because they are operating longer than necessary.
- The best way to warm up a car's engine and interior is by driving, not idling.
- For every hour of idling, 1/5 to 7/10 of a gallon of fuel is burned away.
- Turning off and restarting vehicles does not burn more fuel, nor causes more engine damage than idling. Ten seconds of idling burns more fuel than shutting down and restarting.
- For every 10 minutes a vehicle's engine is turned off, one pound of carbon dioxide is not being released into the atmosphere.