The battle between natural and mechanical ventilation will be among the main events at ASHRAE’s annual meeting.

“Natural Ventilation in Schools: Boon or Bust?” is slotted for 8 a.m. June 24 during the American Society of Heating, Refrigerating and Air-Conditioning Engineers’ meeting in Long Beach, Calif.

“Natural ventilation in schools is used to lower cooling and ventilation costs,” said seminar chairman Chris Muller of Doraville, Ga.-based air-quality equipment maker Purafil Inc. "However, uncontrolled ventilation can allow contaminants to bypass filters and permit the introduction of excess moisture. Given the number of schools located in non-attainment areas for one or more of the U.S. Environmental Protection Agency’s priority pollutants, natural ventilation can present increased health risks to a large segment of the student population.”

Outdoor-air quality and how it affects schools using the cleaning requirements of ASHRAE’s Standard No. 62, which covers indoor air in commercial buildings, will be the focus.

“Although you may expect to pay more for the operation of mechanical HVAC systems vs. natural ventilation, ASHRAE Standard 62.1 provides design options that reduce operating costs while still providing for acceptable indoor air quality,” said Purafil’s Brad Stanley. He will present “Mechanical vs. Natural Ventilation in Schools: Less Can be More.”

A case study is planned. North East Independent School District official Jerry Lamping will explain how the San Antonio school system doesn’t use conventional air conditioning in locker rooms and gymnasiums, instead opting for natural and mechanical ventilation.

District voters are scheduled to soon vote on a bond issue that would allow air conditioning to be installed.

The Lawrence Berkeley National Laboratory’s Michael G. Apte, Ph.D., will discuss “Ventilation Considerations in Areas with Elevated Ozone Levels.”

“As we get more information on reactions by oxidants to organic compounds and their by-products, the rationale to control ozone entry into buildings and to select materials less prone to ozone reactions becomes stronger,” he said.

For more information visitwww.ashrae.org/longbeach