A string of 11 hazardous, bad-air days was the longest in the San Joaquin Valley since 1998, when air officials designated 14 unsafe days for children to play outside. Only Los Angeles – with 18 health advisories – had more health warnings this year.

CANCELED: Signs at Buchanan High School announce changes in the sports schedule due to bad air Sept. 13 in Clovis. This was the first time in recent memory Friday night football was disrupted. (Kurt Hegre / The Fresno Bee)

When ozone levels reach 145 parts per billion for an hour, the San Joaquin Valley Air Pollution Control District issues a health advisory and notifies school officials to cancel outdoor recesses and sporting events.

State-ordered health advisories affect everything from after-school swimming classes to tennis practice, but for the first time in recent memory, deteriorating air quality interrupted Friday night football in the Valley. Junior varsity games from Fresno to Parlier and as far south as the foothills outside Bakersfield were called off Sept. 13.

"We've had practices postponed," says Clovis West coach Carl Scudder. "But we've never had a game canceled or postponed or affected by air quality."

The players were disappointed, but safety comes first, Scudder says: "In addition to the kids I'm coaching, I also have two kids I'm raising. And the [air pollution] problem doesn't seem to be getting better; it seems to be getting worse."

A health advisory is different from the air district's "Spare the Air Day" program. On "Spare the Air" days, schools can opt to keep children inside – but it's not mandatory. Health advisories carry the weight of law, though no one checks to ensure schools obey these health orders.

Overall, school officials take the health advisories seriously. But getting the word to principals and coaches in time to protect children remains a problem.

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Ozone concentrations climb slowly throughout the day in the Valley. Smog levels usually spike after 3 p.m. By the time air pollution officials declare a health advisory, elementary students are on their way home and high school athletes are on practice fields.

Health advisories go out by fax and e-mail to schools. The air district also alerts radio and television stations and newspapers when conditions are unhealthy. "Short of an air raid alarm, this is the best way to do it," air district spokeswoman Josette Merced Bello said on a health-advisory day in August.

Still, children can be caught outside on smoggy afternoons, as was the case Aug. 13. While girls on the Hoover High School tennis team warmed up at an after-school practice, temperatures soared to 106 degrees and ozone peaked at 147 ppb, high enough to trigger a health advisory.

Tennis players and coaches were unaware of the unhealthy ozone levels until 15 minutes into practice, when Athletic Director Doug Semmen received an e-mail message directing him to bring athletes indoors.

Semmen dashed to the sweaty players, issuing a curt order: "Everybody off the court."

The urgency of getting children indoors during smog episodes is well-documented. Shortness of breath and burning lungs are two immediate health problems. Long-term exposure to ozone can scar lungs and stunt lung development, and may cause asthma in athletic children.

The California Air Resources Board created the ozone health advisory in 1990 to address health concerns. At that time, the board lowered the health notification level from 200 ppb to 145 ppb to protect "young children and healthy adults who exercise vigorously during high-pollution levels."

This year, the state is reviewing ozone standards, including the current health advisory regulation. The review could result in tightening of rules to better protect children, but the findings won't be available until 2003 or 2004.

Stricter ozone standards likely would trigger more health advisories.

Thus far, 11 health advisories in 2002 and 14 in 1998 are the highest number of smog warnings issued in the Valley. Only one advisory was issued in 2001, three in 2000 and none in 1999 and 1997.

Years of double-digit health advisories could become the norm, however, as ozone levels remain static or creep upwards.

The Valley has all the ingredients needed for smog: hot, stagnant summers and plentiful vehicle exhaust. Ozone, the chief ingredient of smog, forms best on hot, calm summer days when the sun cooks chemicals discharged from car and truck tailpipes and other combustion sources.

Sending children to school in August, one of the hottest and smoggiest months, doesn't make sense, say some Fresno parents. Five of this year's 11 health advisories occurred in August. Three advisories occurred in July and three in September.

"The middle of August is hot. It's miserable; it's no environment to learn in. And one of the dangerous things is the triggering of soccer and all the other sports two to three weeks before that," says Fresno parent Wendy Carroll.

Carroll helped collect signatures on a petition in 2000, asking Fresno Unified School District officials to change the start of school from August to September. The petition-drive failed, but Fresno Unified School District officials did add three parents to a committee that decides the school calendar.

"We got very hot and bothered on one hot, August afternoon and decided to go to the school and find out why our kids were starting school so early and starting sports so early," says Carroll.

The parents heard several arguments against a September start date. The hardest position to fight: Children without air-conditioning or evaporative coolers in their homes benefit by being at school in August.

She isn't against helping children who live in poverty, Carroll says.

But she doesn't want to rely on health advisories to protect her child from harmful smog:

"I know it takes a village to raise a child, but I also have to raise my own child."