510876.fig.0023a
(a)
510876.fig.0023b
(b)
Figure 23: Growth of 218Po, 214Pb, 214Bi, and 214Po initiated by α-transformation of 222Rn (initial activity concentration of 1 Bq m−3, equivalent to 0.477 radon atoms cm−3), expressed in: (a) activity concentration and (b) number concentration of RnDP atoms.