It may be more difficult to accurately determine the level of potentially harmful radon gas in a school than in a home, a new and unpublicized report by the Environmental Protection Agency suggests.
Findings from the report, which includes testing data from five Fairfax County, Va., schools, indicate that the methods commonly used to test homes for radon may not yield accurate readings for schools.
The study found that, unlike homes, rooms on the same level of a school building may contain significantly different amounts of radon. It also found that concentrations of the gas were lower during classroom hours than on weekends, when many schools do their testing.
In addition, the study concluded that an inexpensive short-term test commonly used by schools may yield slightly higher readings than those obtained by a more sophisticated three-month detector.
The epa report was completed last month, but has not yet been distributed beyond the agency’s regional offices.
The report’s significance is underscored by the fact that a federal measure requiring the epa to conduct a national survey of radon levels in schools now awaits President Reagan’s signature.
The $45-million omnibus radon law, which earmarks $1.5 million for the survey and radon-mitigation efforts for schools, received final ap4proval only a month after federal health and environmental officials advised all homeowners to test their houses for radon.
Although the federal health advisory does not apply to schools, epa officials recommend that schools in neighborhoods where high levels of radon are found undergo radon testing.
Radon is an odorless and colorless natural gas that seeps into buildings through their foundations. Scientists believe it poses a serious health threat and can cause lung cancer.
The new law “really places a premium on establishing a reliable protocol for schools to test for radon,” said Kirk Maconaughey, chief of the problem-assessment branch of the epa’s radon division.
He said the agency expects to develop an interim guidance document on testing procedures for schools--one that includes the results of the new report--by December.
Testing on the five Virginia schools was conducted this past spring. Four of the schools were thoroughly tested; only several rooms in the fifth were tested because school officials there had already undertaken efforts to reduce radon levels.
The federal investigators used three different types of instruments to measure radon levels: two-day charcoal canisters, an inexpensive detection method commonly used to determine if further tests are needed; a continuous monitoring device that was used to measure radon levels for 16 days; and three-month “alpha-track detectors,” which contain plastic strips that are altered by the energy released by decaying radon.
According to the report, investigators found that all four schools averaged less than 4 picocuries of radon per liter of air, the level at which the agency recommends that corrective action be taken. However, three schools had at least one room that exceeded this recommended level.
A picocurie represents one-trillionth of a curie, the standard measuring unit of radioactivity.
The researchers also found that the alpha-track detectors uncovered lower levels of radon than did the charcoal canisters.
“If someone was doing just a two-day test, he may hit the wrong two days, which could be unusually low or unusually high,” said Mr. Maconaughey.
"[The report] is really breaking new ground,” he continued. “This is an area in which there is not a wealth of information.”
“A lot of schools have been modifying the procedures we’ve been recommending for homes, but what we found was that this may not be the most beneficial and advantageous way to measure schools,” he said.
In addition to developing the interim guidelines for measuring radon, agency officials said they have put together a list of 800 companies that have passed the epa’s voluntary radon-testing proficiency program. Schools can obtain a copy of this list by contacting their regional epa office.
Federal officials said they would also develop a similar program by next year to assess firms that perform mitigation work.
The epa has also begun to offer three-day training classes on radon measurement and mitigation in eight states.
In addition, several states have begun to take a greater interest in the area. In Florida, for example, a bill adopted this year requires all public and private schools to be tested for radon by July 1990, using professionals who have been certified by the state.
The certification regulations, which go into effect in January, require that all prospective consultants take a three-day course sponsored by the state and meet certain other education and radon-experience requirements.
In addition to Florida, Pennsylvania and Nebraska have certification requirements in effect for radon specialists. Maryland and New Jersey will have such regulations in place by January.
Similar bills are pending in four other states’ legislatures.
