Oxygen Saturation Concentration

The amount of oxygen that can be dissolved in water is a function of temperature, concentration of dissolved solids, and atmospheric pressure. An equation developed by APHA (1985) is used to calculate the saturation concentration of dissolved oxygen:

$Ox_{sat}=exp[-139.34410+\frac{1.575701*10^5}{T_{wat,K}}-\frac{6.642308*10^7}{(T_{wat,K})^2}+\frac{1.243800*10^{10}}{(T_{wat,K})^3}-\frac{8.621949*10^{11}}{(T_{wat,K})^4}]$

4:5.3.2

where $Ox_{sat}$ is the equilibrium saturation oxygen concentration at 1.00 atm (mg $O_2$/L), and $T_{wat,K}$ is the water temperature in Kelvin (273.15+°C).