Chalfen said the type of complaints made about the CRLS facility are common to buildings built in the late 1970s. At that time, many structures were built with sealed windows and inadequate ventilation in an effort to conserve energy, resulting in the so-called "sick building" syndrome, he said.

"We have always given high priority to the problem of poor air quality," said School Committee member Larry Weinstein. "Now we must give it our highest priority. We've moved it to number one on the agenda."

Air Tested in 1985

In 1985, Dr. Francis Berlandi of Touchstone Environmental Consultants tested the school's air for silicone, sulphur, chloride, iron, calcium, volatile organic compounds, formaldehyde, pesticides, carbon monoxide and airborne bacteria, but according to Giroux he did not find higher than normal concentrations of any of these. However, ventilation was found to be poor, Giroux added.

The school system has made several attempts to improve the ventilation system, Giroux said. Officials cleared clogged ventilation shafts, replaced broken fans and added new fans in parts of the school with poor circulation, Giroux said.

In addition, several experts who have visited the school have concluded that the extent of the problem was limited to ventilation. Giroux said that in 1983, a committee from the state found a high, but non-toxic level of carbon dioxide at the school. Later that year, David A. Link, chief of pediatrics at the Harvard-affiliated Mt. Auburn Hospital, confirmed those results.

Over the last five years, officials from such groups as the federal Center for Disease Control, Applied Researches Group and a maintainance engineer with Johnson Controls inspected the building and determined that ventilation was the main problem.