The problem of high radon levels in Pennsylvania came into the public limelight in 1985 when the Pennsylvania Bureau of Radiation Protection received a report of a home in eastern part of the state with an alarmingly high level of radon daughters.
Extent of the Problem
When the Radiation Protection Bureau launched a large-scale radon monitoring, educational, and resolution effort, it led to a screening of more than 18,000 homes between 1985 and 1986 for radon daughters. Nearly 60 percent of these homes had indoor radon levels in excess of the safety guideline of 0.020.
It was recognized that in Pennsylvania, geologic regions with higher levels of uranium ore were prone to potential indoor air pollution due to the naturally occurring radon gas. Homes in the vicinity of radium extraction facilities were also exposed to elevated levels of radon.
Risks from Radon*
A number of studies and surveys in Pennsylvania conducted over the years attempted to determine the exposure and risk of lung cancer due to radon pollution. The National Council on Radiation Protection and Measurements (NCRP) issued two reports on radon and radon daughter exposures, which helped evaluate the risk of exposure to home residents in the state.
It was found that risk of lung cancer due to constant exposure to 13 Working Levels (WL) of radon within one year is 0.13. In other words, the chances of attaining lung cancer in such a scenario are 13 out of 100. This is an alarming figure, which makes it critically important to ensure that homes are located away from the areas that are heavily exposed to radon and radon daughters.
Actions from the State Government
The government swung into action when it was conclusively found that a particular home had dangerously high levels of radon. The particular test home was vacated immediately, and the authorities helped in providing alternative living arrangements to the affected family until corrective measures in the home could be put in place.
The isolated event prompted the Radiation Protection Bureau to conduct a house-to-house survey to determine radon levels in the vicinity of that home. However, in absence of any scientifically established standards for exposure to radon for the general population, it became a challenge to determine how much exposure is dangerous to human health.
Recommended Guidelines
The Radiation Protection Bureau in Pennsylvania recommends a yearly exposure guideline of 2 WL Months. This is equivalent to a continuous exposure level of 0.04 บ้านมือสอง กรุงเทพ WL. However, the Environmental Protection Agency (EPA) along with CDC has recommended a guideline of 0.02 WL. But these agencies, certainly the EPA, have lost an abundance of credibility with the manner they view people's rights and business freedom over the years. Therefore, the Bureau should be given a little more credence in this case.
The recommended action guidelines to cut down exposure to radon daughters suggest that if the exposure is found to be in the range of 0.5 to 1 WL, the residents should take necessary corrective action within two weeks to lower the levels as far below 0.5 WL as possible.
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