An approach to predicting indoor radon concentration based on depressurisation measurements

Abstract

Exposure to radon is recognised as the second-leading cause of lung cancer after tobacco smoke. The passive measurements typically take up to three months to be representative of the annual radon concentration. A recently developed approach depressurises a dwelling to heighten the convective radon flux determining radon entry rate coefficients. The current study characterises the ventilation status, air tightness and eight selected hourly air change rates measurements, of a sample of naturally ventilated dwellings in Ireland. The household averaged air change rate ranged from 0.28 to 1.87 h−1 and airtightness measurements ranged from 4.830 to 9.423 m3 h−1 m−2 @ 50 Pa, depending on the building characteristics. The experimentally obtained values were used to parameterise a computational model for these selected dwellings and to predict radon concentrations. The radon entry rate power laws ranged from 0.18ΔP0.97 to 1.28ΔP1.18 Bq s−1. Probabilistic functions were generated based on the experimental data and predicted radon concentrations were within one standard deviation of the experimentally measured values in three out of four cases. The data generated can be used in modelling simulations to predict indoor radon concentrations based on local meteorological conditions, building characteristics, ventilation guidelines and energy-retrofit measurements.

Evaluation of the effect of cover layer on radon exhalation from building materials

“…Many experimental research and modelling had been undertaken to predict and reduce the radon exhalation rate from building materials. [14][15][16][17][18][19] Hatungimana et al 20 studied the effect of partial cement replacement with silica fume and fly ash, on the surface radon exhalation rate of mortar mixtures. The results showed that the surface radon exhalation rate is reduced with an increase of silica fume containing in mortar mixtures and the surface radon exhalation rate is increased with a reduction of fly ash containing in mortar mixtures.…”