All radon mitigation systems should be designed to reduce the radon concentration in each livable area within the footprint of the building As Low As Reasonably Achievable.
3.9 pCi/l is NOT the Goal!
IT IS A MYTH that the target radon level is 3.9 pCi/L. The goal is As Low As Reasonably Achievable [ALARA]. According to EPA and ASTM it is reasonable to achieve levels below 2.0 pCi/L with a fan-powered system.
Mitigators who set 3.9 pCi/L as their reduction goal, rather than making every attempt to obtain the lowest reasonably achievable level are not acting in the consumer’s best interest. Remember: there is no safe level of radon.
Radon mitigation specialists are not required to lower all radon levels below 4.0 pCi/L. ALARA allows for spaces that are extremely difficult, if not impossible to reduce below the action level.
Mitigation is not always “one and done”
Sometimes a mitigator needs to return to the site to make adjustments to the fan motor or add secondary and tertiary suction pits to achieve the lowest achievable radon level.
Passive Systems Can Work
Studies now show that Passive Mitigation “Systems”, if installed properly, can be effective up to 70% of the time.