My Woodbury home has a passive radon system. Do I still need to test?

Yes. Many newer Minnesota homes were built with a passive radon-resistant rough-in, a vertical pipe routed from beneath the slab up through the roof that relies on natural airflow to vent soil gas. That passive system reduces radon for some homes but does not guarantee levels below the EPA action level, and it can't be assumed effective without measurement. The only way to know whether the passive rough-in is keeping your radon low is to test with a 48-hour continuous monitor in the lowest livable level. If the result is still elevated, the good news is that a passive rough-in makes activation simple: a technician adds an inline fan to turn it into an active sub-slab depressurization system, usually at lower cost than installing a system from scratch. In high-radon Washington County, never treat the presence of a pipe as proof of safety. Test, then activate only if needed. To add radon testing to your inspection, build a free instant quote online.