Ina Shlez: Smog is Worse this Time of Year

Ah, summertime! The season of backyard barbeques, baseball and fog has finally arrived in San Francisco.

But there's another way that we know that it's summertime - when we look at the horizon and see a dark brown haze hovering over the bay.

Many northern Californians don't think smog is a problem here. But smoggy days are a reality here in the Bay Area - not just in the nether regions of our state. As a matter of fact, The Environmental Protection Agency lists the Bay Area as out of compliance with the Clean Air Act.

Good Ozone, Bad Ozone
Ozone's a good thing when it's high up in the atmosphere. But ground-level ozone - which is what smog is - is a dangerous substance that can affect our health and environment.

Smog is formed when potent air pollutants combine, a condition made worse by hot temperatures and low winds. Smog causes health problems, like coughing, wheezing, chest pains and asthma attacks.

The people at greatest risk are children, the elderly and those with existing medical conditions. However, even a healthy person doing strenuous outdoor activities can become affected. It's well known that emergency room visits for cardiovascular and respiratory ailments increase significantly on smoggy days.

Spare the Air!
The good news is that there are simple things we can do to prevent smog. You can start by looking for Spare the Air warnings on TV, in the newspaper, on highway signs and on the Internet.

Spare the Air tells you when the forecast calls for conditions that are likely to result in smog. Usually this happens when the temperature rises, the wind is low and there's no fog.

How to Prevent Smog - What Can We Do?
Most smog-forming pollutants come from sources we can exercise some control over. For instance, more than 550 tons of nitrogen oxide comes from Bay Area cars and trucks each day - so the best thing we can do on a Spare the Air day is leave the vehicle at home. Take public transit, carpool or, if possible, bike or walk to work. If you must drive, plan your day so that you can run all your errands in one trip. Link your stops to make them in a logical order and then leave your car at the curb or in the driveway for the rest of the day. Starting your car repeatedly, especially on a cold engine, is one of the worst things you can do on a bad ozone day.

Another way we can help is to avoid filling our gas tanks during hot daytime hours. A significant amount of fuel escapes as vapor every time we open the gas tank, which contributes to ozone formation.

Gasoline-powered equipment, like lawn mowers, edgers, leaf blowers and stationary power generators, also contribute to smog-formation. Wait a few days for the air to improve before using this equipment.

Alas, we should also avoid barbequing on Spare the Air days. Whether you use charcoal or propane, you're releasing smog-forming compounds. If you really must flip a burger, wait until evening when it's not as hot and the sun is not as strong.

Paints, insecticides, hair spray, furniture polish and cooking sprays all contain chemicals that form smog. Try to avoid these products on Spare the Air days as well.

When temperatures rise and air conditioners are working at full blast, electricity generation rises to meet the demand - and power plants are among the biggest sources of air pollution. When power stations have to work extra hard, they puff more pollution out of their smokestacks.

For More Information
For more information about Spare the Air days and how you can get notified, call 1-800-HELP-AIR or visit www.sparetheair.org. Also, keep your eyes and ears open for the Spare the Air warnings usually broadcast on television and radio stations and announced in the newspapers.

Ina Shlez is clean air specialist for SF Environment, where she coordinates projects like Car-free Day and Spare the Air. Learn more about how the City is working to make a safer, healthier environment at wwwsfenvironment.com, visit the EcoCenter at 11 Grove St. or call (415) 355-3700.