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Determination of representative elementary surface for accurately measuring radon exhalation rate in masonry wall

  • 0National & Local Joint Engineering Research Center for Airborne Pollutants Control and Radiological Protection in Buildings University of South China, Hengyang 421001, Hunan, China.
Journal of Hazardous Materials +

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November 26, 2024

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November 26, 2024

View abstract on PubMed

Summary

This summary is machine-generated.

Accurately measuring radon exhalation from building walls requires identifying a representative elementary surface (RES). This approach accounts for differing radon rates from bricks and mortar, improving radon protection evaluations.

Area Of Science

  • Environmental Science
  • Building Physics
  • Radiological Protection

Background

  • Indoor radon concentration is influenced by building wall surface radon exhalation rates.
  • Accurate measurement is crucial for effective radon protection strategies in buildings.
  • Masonry walls, composed of bricks and mortar, exhibit varying radon exhalation properties.

Purpose Of The Study

  • To investigate radon exhalation rules on masonry wall surfaces using Computational Fluid Dynamics (CFD).
  • To determine a method for accurate measurement of average radon exhalation rates from building walls.
  • To address the impact of measurement tool positioning and size on radon exhalation rate data.

Main Methods

  • Computational Fluid Dynamics (CFD) simulations were employed to model radon exhalation.
  • Simulations considered both diffusion and seepage-diffusion conditions on wall surfaces.
  • Experimental validation confirmed the accuracy of the proposed measurement approach.

Main Results

  • Radon exhalation rates differ significantly between brick surfaces and cement mortar joints.
  • A representative elementary surface (RES) is essential for accurate average radon exhalation rate measurement.
  • The shape of the RES is flexible, and its area can be a multiple of the fundamental RES area.

Conclusions

  • The concept of a representative elementary surface (RES) enables precise average radon exhalation rate determination for masonry walls.
  • Integrating radon exhalation rates from brick-mortar interfaces using RES improves building radon protection design.
  • The study validates the effectiveness of the RES method through experimental confirmation.

Keywords:

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