General liability protection, once elusive to professionals who test and clean up buildings contaminated with high levels of radon, is now on the market.

The coverage is offered by New York-based Reliance National Risk Specialists through insurance broker Bowers, Schumann & Welch Insurance, of Bethlehem, Pa."There was continuing concern about reasonably priced coverage. Not one company wanted to write the coverage with the limits that we wanted," said Jim Craffy, executive secretary of 1,000-member American Association of Radon Scientists and Technologists, of Park Ridge, N.J.

The new joint insurance offering is available only to association members. Other qualifications include state certification, participation in the EPA's Radon Program and adherence to the association's guidelines for radon testing, mitigation and laboratories.

The Reliance-Bowers insurance program has a annual pay-out limit of $1 million on individual as well as aggregate claims awards, said Robert J. Philhower, assistant vice president of special programs at Reliance. There is also an annual $1 million maximum limit on claims awards for personal and advertising liability, he said.

Other policy limits include $50,000 for annual fire and legal claims and $5,000 for annual medical expenses.

The public's perception of exposure to the colorless and odorless naturally- produced gas has matured to a level of understanding above the initial hysteria, according to experts in the field. Exposure to the gas formed by the decay of radium and uranium, along with exposure to arsenic and certain organic chemicals, will account for 142,000 of the 510,000 cancer deaths this year, the EPA said.

In the past, insurers have been reluctant to offer liability policies to radon specialists due to the effects of radon exposure, which can develop into lung cancer and take up to 20 years to be detected, Mr. Craffy said.

According to radon mitigation experts, the south central region of Pennsylvania is one of the worst in the nation in terms of radon concentration.

There, the state provides certification programs geared toward the testers and mitigators. If a radon specialist is found to have performed a faulty test or to have incorrectly administered a radon test, the state Insurance Department can decertify the specialist, block the specialist from working for the state and exclude the specialist from its list of recommended radon specialists, said Pam DiSalvo, a spokesperson for the Pennsylvania Department of Environmental Resources.

Pennsylvania is not the only state with a strict certification program. About 14 other states test their radon specialists and require them to adhere to strict standards. Mr. Craffy said that some of his members prefer "strict regulation in lieu of insurance."

His reasoning is there are very few court cases involving radon specialists. Those that do involve real estate, he said.