CTR3LGC returns the CT required from the EPA 3 log inactivation CT Tables.  Uses 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.

SYNTAX:

CTR3LGC(Disinfectant ID, Water Temperature, pH, Cl2 Residual)

Disinfectant ID: Type of disinfectant used for inactivation. Disinfectant has one of the following settings:

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

Water Temperature: Temperature of water in Deg C.

pH: pH of water.

Cl2 Residual: Cl2 Residual in mg/L at the end of the segment.

EXAMPLES:

CTR3LGC(1,C5,D5,E5): Returns  the CT Value for  3 Log Inactivation of Giardia Cysts by free chlorine.

C5	D5	E5	Result of CTR3LGC	EPA Table Value
Temp	pH	Cl2 Residual	CT	CT
25	7	1	37.5	37 (EPA Table C-6)
20	7	1	56.0	56 (EPA Table C-5)
20	7.2	1	60.2	??? (7.2 not in table)