(15)Equation 15 (non-radionuclides), equation 16 (radionuclides), and Table 11 present the exposure variables for the surface water/groundwater inhalation pathway from showering and from indoor water use. This pathway is conducted for the residential and agricultural scenarios only. The industrial and recreational default intake rates are set to 0 m3/day.
(15)
(16)
Table 11. Surface Water/Groundwater Inhalation while Showering Parameters
|
Parameter |
Units |
Residential |
Industrial |
Recreational |
Agricultural |
|
Non-radionuclide chemical concentration in water = Cwn |
mg/L |
Chemical-specific |
Chemical-specific |
Chemical-specific |
Chemical-specific |
|
Radionuclide chemical concentration in water = Cwr |
pCi/L |
Chemical-specific |
Chemical-specific |
Chemical-specific |
Chemical-specific |
|
Volatilization Factor = VF |
L/m3 |
Chemical-specific |
Chemical-specific |
Chemical-specific |
Chemical-specific |
|
Inhalation rate = IRair |
m3/hour |
20 (EPA 1989a) |
0 |
0 |
20 (EPA 1989a) |
|
Exposure frequency = EF |
day/year |
350 (EPA 1991) |
250 (EPA 1991a) |
40 (EPA 1992) |
350 (EPA 1991) |
|
Exposure duration = ED |
years |
30 (EPA 1989a) |
25 (EPA 1991a) |
30 (EPA 1989a) |
30 (EPA 1989a) |
|
Inhalation exposure factor = IEF |
(L hr)/ (m3 day) |
0.2802 (Tritium) 7.603 (Radon) 0 (other radionuclides) |
0.2802 (Tritium) 7.603 (Radon) 0 (other radionuclides) |
0.2802 (Tritium) 7.603 (Radon) 0 (other radionuclides) |
0.2802 (Tritium) 7.603 (Radon) 0 (other radionuclides) |
|
Body weight = BW |
kg |
70 (EPA 1989a) |
70 (EPA 1989a) |
70 (EPA 1989a) |
70 (EPA 1989a) |
|
Conversion Factor = CF9 |
days/hr |
1/24 |
1/24 |
1/24 |
1/24 |
|
Conversion Factor = CF2 |
days/yr |
365 |
365 |
365 |
365 |
|
Lifetime = LT |
years |
70 (EPA 1989a) |
70 (EPA 1989a) |
70 (EPA 1989a) |
70 (EPA 1989a) |
|
Averaging time = AT |
years |
LT (carcinogen) ED (noncarcinogen) |
LT (carcinogen) ED (noncarcinogen) |
LT (carcinogen) ED (noncarcinogen) |
LT (carcinogen) ED (noncarcinogen) |