CTR3LGC is a method for approximating the CT Tables for 3 log inactivation of Giardia Cysts by Free Chlorine.  The CT Tables (from EPA Disinfection Profiling and Benchmarking Guidance Manual) are used to find the CT Required for certain conditions (temperature, pH, Chlorine Concentration, and log inactivation).  This function will return the value from the table for 3 log inactivation given a disinfectant, water temperature, pH, and Cl₂ Residual.

For more informaiton on CT Calculations, click here: Calculating CT in WIMS

SYNTAX:

CTR3LGC(Disinfectant ID, Water Temperature, pH, Cl₂ Residual)
where :
Disinfectant ID is a constant based on the type of disinfectant used for inactivation.  Disinfectant ID has one of the following settings:

1. Free Chlorine
2. Chlorine Dioxide
3. Chloramines
4. Ozone

Water Temperature is the water temperature in Degrees C
pH is the measured pH of the water
Cl₂ Residual is the Cl₂ Residual at the end of the segment

NOTES:

Water Temperature, pH, and CL₂ Residual should be variable inputs and the Disinfectant ID should be set once as a constant.

EXAMPLES:

V84 = CTR3LGC(1, V1021, V1031, V1041)

Variable 84 will contain the CT Value for 3 Log Inactivation of Giardia Cysts by free chlorine.

SEE ALSO: CT, CT Tables, Calculating CT in WIMS