system in our basement. We are currently having someone dig out our crawlspace area (about 300 sq ft) to make into a storage/workout room. They are recommending we install another, separate mitigation system for about $2500.

Couple questions -

I understand the danger/risk of radon in sleeping places or places where you spend a lot of time. We will be using the workout area about an hour a day, is that too much exposure time?

Anyone have experience using those 48 hour testing kits that are sent in for results?

Should the existing system (tied to a sump pump well in the corner of the house) be sufficient to handle the extra 300 sq feet? The door to the storage room will be closed most of the time.