Why is 4 pCi/L the recommended action level for Radon?
EPA recommended this mitigation action level in 1986 for several reasons. First, at lower levels (2 pCi/L) measurement devices false negative errors increase threefold, and false positive errors increase twofold. Secondly, mitigation research indicates that elevated levels can be reduced to 4 pCi/L or less 95% of the time. Research also indicates that 2 pCi/L can be achieved 70% of the time. Further, mitigation technology available today can reduce radon levels to between 2 and 4 pCi/L most of the time. Finally, cost benefit analysis performed in 1986 indicate that an action level of 4 pCi/L results in a cost of about $700,000 per lung cancer death saved. If the action level was set at 3 pCi/L, the cost would be $1.7 million, and if set at 2 pCi/L, the cost would be $2.4 million per lung cancer death saved. EPA states that 4 pCi/L is a recommended action level, but homeowners can further reduce their lung cancer risk by mitigating homes that are below 4 pCi/L.
