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# 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).