Table 3 Simplified formulas and conditions for calculating radon exhalation rate by the closed chamber method.
Simplified formula | Conditions to be met | |
|---|---|---|
\(J = \frac{\lambda V}{{S\left( {1 - {\text{e}}^{{ - \lambda {\text{t}}}} } \right)}}\left( {C - C_{0} {\text{e}}^{{ - \lambda {\text{t}}}} } \right)\) | (1) | The radon leakage and anti-diffusion are ignored |
\(J = \frac{{V\left( {C - C_{0} } \right)}}{St}\) | (2) | â‘ Meet condition (1) â‘¡ \(\lambda t < < 1\) |
\(J = \frac{Vk}{S}\) | (3) | ①Meet condition (2) ② The cumulative radon concentration is linear with the cumulative time, and k is the slope obtained by using the least square method, Bq·m−3·s−1 |
\(J = kH\) | (4) | â‘ Meet condition (3) â‘¡ The radon exhalation surface is consistent with the base area of the radon collector, and the radon collector is cylindrical or cubic. H is the height of the radon collector, m |
