Inhaled progeny of Rn-222 (radon progeny) are the most important source of
irradiation of the human respiratory tract. Their attachment to atmospheric
aerosols follows a well established relationship between the activity size
distribution (ASD) and the number size distribution. Recent studies have s
hown that indoor aerosols are derived primarily from outdoor sources, so it
is pertinent to study the effects of different ambient environments on the
indoor radon dose tin terms of the dose conversion coefficient or DCC, in
units of mSv WLM-1). Commonly encountered ambient aerosols were studied her
e, which included the traffic-, urban-, and marine-influenced aerosols. The
ASDs of attached radon progeny for all three studied ambient environments
were well-represented by normal distributions. From these ASDs, the DCCs we
re calculated using the ICRP66 model and the scaled Yeh-Schum model. All ot
her employed parameters were adopted from original references or authoritat
ive reports. The DCCs for a nominal home calculated using the James model a
nd the Yeh-Schum model were 12 and 8 mSv WLM-1, respectively. The DCCs were
largest for urban-influenced ambient environments and smallest for marine-
influenced ambient environments, and those for traffic-influenced ambient e
nvironments were close to that for a nominal home. If we adopt the stochast
ic model,the probability of contracting radon-induced lung cancer by a pers
on living with a marine influenced ambient environment will be half that of
a person living with an urban-influenced ambient environment.