Trish Hedin didn't know there was a plan to add a cellphone panel to the steeple of the church where her daughter Karlee, 4, goes to preschool until a concerned neighbor near the church handed her a flier.

That's when Hedin and other parents, concerned about risks to youngsters' health, started researching on the Internet the effects of radio waves on small children.

"Cellphone towers could be the lead paint or asbestos issue of the future. There's not enough information about the effects of this on the thin skulls of children, so why take the risk?" Hedin said.

She and other parents went to a board meeting at Christ the King Lutheran Church, 3947 Kimber Drive in Newbury Park, where they asked that the cellphone panel not be added to the steeple of the church near the preschool playground.

"Our health concerns were disregarded. We could not convince the board it wasn't safe, and they could not convince us it was safe," Hedin said.

The pastor of the church, Rev. Tim Eaton, was confident that no one's health would be compromised by the cellphone panel.

"I work about 60 hours a week underneath where they're going to put it, and next year my son is going to be at the preschool," he said. "I don't think it's going to be a health risk."

Eaton said he would be against it if he thought it would be unhealthy for anyone. Many churches locally and across the state, he said, have added cellphone towers or panels to their rooftops.

"Churches are chronically underfunded, and this is an excellent way for a church to get revenue," said Bob Wentworth, vice president of the parish planning committee.

Wentworth said the church did extensive research and talked to other churches that have towers. He explained the decision followed a long, slow process that's taken more than a year to come to the planning commission.

Community Development Director John Prescott said the city is precluded by the federal government from analyzing the effects of electromagnetic radiation. Congress gave the right to set the safety standards to the FCC when the Telecommunications Act was signed in 1996. The city planning commission is allowed to focus only on how the tower looks, keeping it hidden or disguised, and to ensure it meets federal government safety standards.

Jonathon Kramer, a radio frequency engineer and telecommunications attorney, is a consultant for the city, helping to verify that cellphone companies comply with national standards. He's been a city technology adviser for 22 years.

"Most cities don't go to that standard of verification, but Thousand Oaks wants an independent verification of the facts," Kramer said. He looks at frequency, power and antenna orientation to make sure they meet the safety standards set forth by the federal government.

"The city is constrained by the federal government as to what they can and cannot do," Kramer said.

Radio waves behave like light, he said. When the antenna sends out radio waves, they go out like a beam of light from a flashlight. A cellphone antenna is designed so signals are aimed toward the horizon, not at the ground.

The radio waves lose strength in the air, and the farther they move from the antenna, the smaller the signal. In this project, the beam will go somewhere above 30 feet, "way over the top of the playground," Kramer said.

Even if someone were to fly like a bird in the strongest part of the beam, which would be 32 feet in the air and within 11 feet of the antenna, they'd still be safe, according to the FCC, which set the safety standard at 2 percent of what is actually considered safe at 100 percent of the antenna's power, Kramer said.

Radio waves are nonionizing emissions, not ionizing emissions like Xrays, he said. Kramer, an attorney and engineer, said he's not an expert on human health.

According to the federal government, if there is compliance with the FCC rules, nobody will be exposed to radio waves. "It's legal. The city can't do anything more," Kramer said.

But Hedin says the parents can do something if the panel is installed. "If they do this, the parents will have no choice but to move our children to another preschool that doesn't have a cellphone tower. That will be sad, because we love this school," she said.