29 A 90 m basement in a residence is found to be

Last updated: 10/3/2023

29 A 90 m basement in a residence is found to be contaminated with radon coming from the ground through the floor drains The concentration of radon in the room is 1 5 Bq L under steady state conditions The room behaves as a CSTR and the decay of radon is a first order reaction with a decay rate con stant of 2 09 106 s If the source of radon is closed off and the room is vented with radon free air at a rate of 0 14 m s how long will it take to lower the radon concentration to an acceptable level of 0 15 Bq L