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Updated: Aug 29, 2025
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Measuring Carbon-based Contaminant Mineralization Using Combined CO2 Flux and Radiocarbon Analyses
Published on: October 21, 2016
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Design on intermittent ventilation strategy for radon removal in underground space
Journal of Environmental Radioactivity
|September 11, 2022
Summary
Intermittent ventilation significantly reduces radon concentration in underground spaces. This strategy offers substantial energy savings compared to continuous ventilation, especially at lower wind speeds.
Area of Science:
- Environmental Engineering
- Building Science
- Indoor Air Quality
Background:
- Radon mitigation in underground structures is crucial for occupant health.
- Ventilation systems represent the largest energy consumers in underground buildings.
- Understanding radon migration (production, exhalation, diffusion) is key to effective control.
Purpose of the Study:
- To propose and evaluate a novel intermittent ventilation strategy for mitigating radon concentration in underground spaces.
- To compare the effectiveness of intermittent, continuous, and no ventilation strategies.
- To analyze the impact of wind speed and fresh air ratios on radon mitigation and energy consumption.
Main Methods:
- Development of a numerical model simulating radon production, exhalation, and diffusion.
- Comparative analysis of three ventilation strategies: none, continuous, and intermittent.
- Simulation under varying wind speeds and fresh air ratios.
Main Results:
- Intermittent ventilation drastically reduces radon concentration startup time compared to continuous ventilation (up to 92.8% reduction).
- Higher fresh air ratios lead to lower radon concentration limits and faster equilibrium.
- Reducing fresh air ratio during intermittent ventilation enhances heat recovery and reduces HVAC energy demand.
Conclusions:
- Intermittent ventilation is a highly effective strategy for radon reduction in underground spaces.
- Optimized intermittent ventilation plans, particularly at low wind speeds, offer significant energy savings.
- Low wind speed intermittent ventilation provides benefits of reduced noise and improved comfort.
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