|Mean PM2.5 concentrations measured in smoking and nonsmoking casino areas and the outdoors|
|PM2.5 Concentration,c μg/m3|
|Casinoa||Type of Nonsmoking Areab||Smoking Area, S||Nonsmoking Area, NS||S-NS Difference||Outdoorsc||NS-Outdoors Difference||Date of Visitf|
aFor all casinos
b“Enclosed” nonsmoking (NS) areas were in a different room that had enclosing walls limiting direct air flow from smoking (S) areas; “Partial” (partially separate) NS areas were in a different room but had no barriers to air flow from the smoking areas; “Open” NS areas were in the same room and not physically separated from the main casino smoking areas.
cA SidePak calibration factor of 0.29 was used for the original PM2.5 indoor measurements in Casinos F, H, I, and J (smoking or nonsmoking). This factor for SHS was determined through a controlled car-cabin (indoor) test and also corroborated with a field test inside a casino . It is expected that the factor applies to all indoor locations, since SHS is likely the predominant aerosol in both smoking and nonsmoking areas. For outdoor aerosol, the factor’s value is assumed to be comparable. based on the work of others [20,21], but could be higher depending on conditions. Regardless, since the absolute outdoor concentrations are small, any resulting error is expected to be low. For example, with an increase in the factor of 2/3, the concentrations would average 5.5 instead of 3.3 μg/m3, an increase of only 2.2 μg/m3.
dThe Jiang et al.  study designated Casino B NS area as Partial, but on our trip it was determined to be Open. During our visit, the NS area was on the main floor off to the side of the main smoking area in a corner of the casino.
eCasino D has a separate NS area that was closed during our visit but was visited by Jiang et al. .
fDate of visit is given on which PM2.5 was measured in MM/DD/YY format. All visits took place on Friday or Saturday early or late evenings or in the early morning hours of the following day, except for Casino G, which was visited in the early evening on a Monday.
Klepeis et al.
Klepeis et al. BMC Public Health 2012 12:819 doi:10.1186/1471-2458-12-819