A 90-m³ 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- (becquerels per liter) under steady-state conditions. The room behaves as a CMFR, and the decay of radon is a first-order reaction with a decay rate con- stant of 2.09 x 10-s. If the source of radon is closed off and the room is vented with radon-free air at a rate of 0.14 ms, how long will it take to lower the radon concentration to an acceptable level of 0.15 Bq -L-¹?

A 90-m³ 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- (becquerels per liter) under steady-state conditions. The room behaves as a CMFR, and the decay of radon is a first-order reaction with a decay rate con- stant of 2.09 x 10-s. If the source of radon is closed off and the room is vented with radon-free air at a rate of 0.14 ms, how long will it take to lower the radon concentration to an acceptable level of 0.15 Bq -L-¹?

Structural Analysis

6th Edition

ISBN:9781337630931

Author:KASSIMALI, Aslam.

Publisher:KASSIMALI, Aslam.

Chapter2: Loads On Structures

Section: Chapter Questions

Problem 1P

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(4) [Text-problem 4.29] A 90-m³ 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- (becquerels per liter) under steady-state conditions. The room behaves as a CMFR, and the decay of radon is a first-order reaction with a decay rate con- stant of 2.09 × 10-6 s-1. If the source of radon is closed off and the room is vented with radon-free air at a rate of 0.14 m³ s-1, how long will it take to lower the radon concentration to an acceptable level of 0.15 Bq L-¹?
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