Cost assessment of ventilation and averted dose due to radon in dwellings

Radon and Its Short-Lived Products in Indoor Air: Present Status and Perspectives

“…Figure 2 presents radon and thoron sub-chains. 218 Po and 216 Po are formed as positively charged and become neutralised in one of the following processes [13][14][15]: (i) recombination with ions produced by α, β, and γ emissions and recoil atoms during radioactive transformations of airborne radionuclides, as well as by background γ and cosmic rays, (ii) electron scavenging by OH radicals formed by radiolysis of water molecules, and (iii) charge transfer from molecules of lower ionisation potential. The states of 218 Po, 216 Po, and their oxides at the moment of their α-transformation into Pb are decisive because they determine the initial characteristics and behaviour of the subsequent members in the chains.…”

“…218 Po and 216 Po are formed as positively charged and become neutralised in one of the following processes [13][14][15]: (i) recombination with ions produced by α, β, and γ emissions and recoil atoms during radioactive transformations of airborne radionuclides, as well as by background γ and cosmic rays, (ii) electron scavenging by OH radicals formed by radiolysis of water molecules, and (iii) charge transfer from molecules of lower ionisation potential. The states of 218 Po, 216 Po, and their oxides at the moment of their α-transformation into Pb are decisive because they determine the initial characteristics and behaviour of the subsequent members in the chains. For 218 Po in 50% humid air at an ionisation rate of 3.2 pC kg -1 s -1 (45 µR h -1 ), the rate constants of the above processes of neutralisation are 0.07 × 10 -2 s -1 , 1.07 × 10 -2 s -1 , and 0.4 × 10 -2 s -1 , respectively, and, eventually, more than half of the species (molecular clusters) are neutral [16].…”

“…The states of 218 Po, 216 Po, and their oxides at the moment of their α-transformation into Pb are decisive because they determine the initial characteristics and behaviour of the subsequent members in the chains. For 218 Po in 50% humid air at an ionisation rate of 3.2 pC kg -1 s -1 (45 µR h -1 ), the rate constants of the above processes of neutralisation are 0.07 × 10 -2 s -1 , 1.07 × 10 -2 s -1 , and 0.4 × 10 -2 s -1 , respectively, and, eventually, more than half of the species (molecular clusters) are neutral [16]. The clusters of RnP and TnP species are called unattached RnP and TnP.…”

Limited applicability of cost–effectiveness and cost–benefit analyses for the optimization of radon remedial measures

“…different remedial action. After detailed consideration, we chose the simplest remedial action -natural ventilation -for the comparison (also used by Katona et al [22]). To be as effective as the original measures studied here, natural ventilation must ensure a ventilation rate that decreases the indoor radon concentration to the same level as the studied measures or at least to the action level of 400 Bq/m 3 .…”

The Effect of Air Filtration on the Fraction of Unattached Radon Products

“…One of the procedures to achieve this aim is ventilation, because it is a dominant parameter controlling Rn and RnP levels indoors [3]. Nevertheless, when applying this mitigation measure, cost-effectiveness should be borne in mind, as more fresh air requires enhanced heating in wintertime [4]. Low RnP levels can also be assured by air-conditioning [5], [6] and by air filtration using special filters [5], [7]− [9].…”