It should be noted that the EPA believes that any radon exposure carries some risk of causing lung cancer; no level of radon can be called safe.  As stated in the post “is radon a health hazard” the Surgeon General has warned that radon is the second leading cause of lung cancer in the US.   Even radon levels below the EPA guideline of 4 pCi/L pose some risk; you can reduce your risk of lung cancer by lowering the radon level in your home.

The following are the general recommendations based on the results of radon testing. The amount of radon in the air is measure in “picocuries of radon per liter of air” or “pCi/L”.

Short term testing with levels LESS THAN 4.0 pCi/L – The EPA does not recommend any follow up action or mitigation.

Short-term testing with levels NEAR 4.0 pCi/L – A second short term test may be in order.  If you do a 2nd short-term test the 2 values should be averaged and if the average is LESS THAN 4 pCi/L no follow up action or mitigation is recommended.

Short term testing with levels EQUAL TO or GREATER THAN 4.0 pCi/L- The EPA recommends mitigation to reduce radon levels.

Some additional information about radon levels and recommendations by the EPA
The average indoor radon level is estimated to be about 1.3 pCi/L and the outdoor level is estimated to be about 0.4 pCi/L.  The US Congress has set a long-term goal that indoor radon levels be no more than outdoor levels.  While this goal is not yet technologically achievable in all cases, most homes today can be reduced to 2.0 pCi/L or less.
Pillar to Post uses professional radon monitoring devices which have been classified as a “Continuous Radon Monitor” testing devices which have been evaluated and accepted by the US Environmental Protection Agency (EPA). The unit must be in place for a minimum of 48 hours.

My next post will address the mitigation methods used in home with high radon levels.