Thoughts On My “Idle” Time

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By Amy Miller

My daughter will be coming out of dance class in just two or three minutes. My aging mother will not want to get into a hot stuffy car. Excess heat, or cold, is not good for the office computer on the backseat. It will cost more in gas to stop then start the car again than to keep it running.

I convince myself – rationalize – that it is OK- for all number of reasons – to leave the car engine running while I am in fact sitting still.

I have read, I have even written press releases, about how much pollution we add to the air by letting our cars idle. And yet.. and yet.. it’s just so darn cold sitting in a quiet car in the dead of winter.

In fact, it is illegal in Massachusetts to leave a vehicle engine idling for more than five minutes. And many other states and individual towns and cities have their own laws along these lines. In Maine, Bar Harbor forbids idling for more than five minutes. The state of Vermont has a law similar to Massachusetts’ that is only in effect from April to November.

The science behind these laws is clear. EPA estimates that exhaust from passenger vehicles is the top source of air pollution in many of the cities in this country. Besides the health risks associated with gasoline fumes, diesel exhaust from idling trucks and buses can make asthma and bronchitis worse. Exhaust also adds to smog, acid rain and global climate change.

So adding to it when a car is parked is just silly. Those of us sitting in an idling vehicle are actually more threatened by the pollution than the people around us.

The law in Massachusetts, and most similar laws, makes exemptions.  For instance some types of delivery trucks, vehicles being serviced, and vehicles that must run their engines to keep refrigeration units cold are all exempt. While it is unclear how much police can and do enforce the laws, tickets in the Bay State can run up to $25,000 for repeat offenders.

To deal with people like me, people who like to grasp on to rationalizations, EPA offers a few factoids: Recent studies found fuel consumption during engine start-up is equal to about 30 seconds of engine idling if the engine is within normal operating temperature. Furthermore, running an engine at idling speed causes twice the wear on internal parts compared to driving at regular speeds.

So next time you are aching to idle, turn your car off and reward yourself by putting a few more dimes into your latte jar.

Find out which states have restrictions on idling:

About the author: Amy Miller is a writer who works in the public affairs office of EPA New England in Boston. She lives in Maine with her husband, two children, eight chickens, dusky conure, chicken-eating dog and a great community.

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