(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 x 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, how long will it take to lower the radon concentration to an acceptable level of 0.15 Bq L-¹?

(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 x 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, 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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Integrated Solid Waste Management

Integrated Solid Waste Management (ISWM) is a thorough waste suppression, compost, removal and recycling Program. An effective ISWM system considers how to suppress, manage and recycle solid waste in a manner that is most efficiently to protect human health and the surrounding. ISWM system requires evaluation of public wants and demands and then selecting and merging the most effective waste management activities for the proposed demands. The main ISWM activities for solid waste management are Waste prevention, Recycling and Composting, and Combustion and Removal and waste collection in a properly planned, constructed, managed and mitigated landfill areas. Each of these requires careful designing, financing, accumulation, and delivery of activities.

Question

(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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