Environmental Engineering Reference
In-Depth Information
Table 4.8
Median and Maximum Concentrations of 12 VOCs Observed at
the Highest Concentrations in the USEPA BASE Study of 56 Randomly
Selected Office Buildings
Median concentration
(
Maximum concentration
(
VOC
µ
g/m
3
)
µ
g/m
3
)
Acetone
29.0
220.0
Toluene
9.0
360.0
d
-Limonene
>0.1
140.0
m
- and
p
-Xylene
5.2
96.0
2-Butoxyethanol
4.5
78.0
n
-Undecane
3.7
58.0
Benzene
3.7
17.0
1,1,1-Trichloromethane
3.6
450.0
n
-Dodecane
3.5
72.0
Hexanal
3.2
12.0
Nonanal
3.1
7.9
n
-Hexane
2.9
21.0
Source:
From Girman, J.R. et al.,
Proc. Indoor Air '99,
Edinburgh, 2, 460, 1999.
Mean (and median) concentrations of VOCs of individual compounds
in nonresidential buildings tend to be below 50
µ
g/m
3
, with most below
5
. Volatile organic compounds in nonresidential buildings are fewer
in number than those found in residences but are qualitatively similar. Con-
centrations tend to be lower (by as much as 50% or more) both on an
individual basis and TVOC (total volatile organic compounds) levels.
µ
g/m
3
C. Sources/emissions
Investigators in North America and Europe have attempted to characterize
emissions of VOCs from building materials and consumer products. VOC
emissions from such products/materials vary with the product as well as
with its manufacturer. Major VOCs emitted from a sample of products are
Most compounds listed in
Table 4.9
are nonpolar substances. Polar sub-
stances, on the other hand, are commonly used in a variety of personal and
home-care products such as colognes, perfumes, deodorants, soaps, deter-
gents, shampoos, air fresheners, and cosmetics. In a study of these materials,
USEPA observed that polar compounds such as ethanol, benzaldehyde,
-
terpineol, and benzyl acetate were found in over 50% of 31 products tested.
In an intensive study of five products (two colognes, one perfume, one soap,
and one air freshener), USEPA confirmed the presence of the above four
compounds as well as
α
-pinene, camphene, myacene, limonene,
diethylene glycol monomethyl ether, linalool,
α
-pinene,
β
-phenethyl alcohol, benzyl
alcohol, estragole, and menethyl acetate in one or more products, with
limonene and linalool found in all five products tested.
β
