We published an article entitled “Analysis of ventilation efficiency as simultaneous control of radon and carbon dioxide levels in indoor air applying transient modelling” in the International Journal of Environmental Research and Public Health in February 2022.
The impact of ventilation efficiency on 222Rn and CO2 concentrations in the indoor air of a residential building was studied by applying transient data analysis within the CONTAM 3.4 program. Continuous measurements of 222Rn and CO2 concentrations and basic meteorological parameters were conducted in a small apartment located in Ljubljana, Slovenia. Throughout the experiment (October 3-15, 2021), frequent ventilation (several times per day), poor ventilation (once to twice per day), and no ventilation were applied, and recorded the exact ventilation and occupancy schedule. Based on the measurements, a transient simulation of 222Rn and CO2 concentrations was performed for six sets of scenarios, where design ventilation rate (DVR) varied based on ventilation requirements and recommendations. The simulation results indicated an optimal DVR of 0.5 ACH (air changes per hour) to ensure CO2 concentration below 1000 ppm and 222Rn concentration below 100 Bq m–3. The presented approach is applicable for various types of residential buildings with high overcrowding rates. A sufficient amount of air volume has to be provided to minimise health risk, which is especially important for protecting sensitive and fragile occupants.