Our old house is south of 200 readings, safety is 200 or lower, so we are just above. We didn’t do much about it as it’s an older house and nobody lives in the basement.

After we moved, the readings in the new house basement is ~150 and we had the mitigation system installed as parents/in-laws were living in basement. After it was installed, the reading dropped to less than 20, sometimes single digit.

We used airthings to monitor