Section Env-Ws 380.16 - Calculation of the Total Inactivation Ratio for Systems That Do Not Provide Filtration(a) If a system owner uses only one point of disinfectant application, the system owner shall determine the total inactivation ratio based on either of the following 2 methods:(1)One inactivation ratio, Ctcalc/CT99.9, shall be determined before or at the first customer during peak hourly flow and if the Ctcalc/CT99.9 > 1.0, the 99.9 percent Giardia lamblia inactivation requirement has been achieved; or(2) Successive Ctcalc/CT99.9 values, representing sequential inactivation ratios, shall be determined between the point of disinfectant application and a point before or at the first customer during peak hourly flow.(b) Under (a) above, the following method shall be used to calculate the total inactivation ratio: (1) The (Ctcalc/CT99.9) shall be determined for each sequence;(2) The (Ctcalc/CT99.9) values shall be added together [SIGMA](Ctcalc/CT99.9); and(3) If [SIGMA] (Ctcalc/CT99.9) > 1.0, the 99.9 percent giardia lamblia inactivation requirement shall have been achieved.(c) If the system owner uses more than one point of disinfectant application before or at the first customer, the system owner shall determine the CT value of each disinfection sequence immediately prior to the next point of disinfectant application during peak hourly flow. The Ctcalc/CT99.9 value of each sequence and [SIGMA] (Ctcalc/CT99.9) shall be calculated using the method in (b) (1) through (3) above to determine if the system owner is in compliance with Env-Ws 380.10.N.H. Code Admin. R. Env-Ws 380.16
#5098, eff 3-18-91, EXPIRED 3-18-97
New. #6521, eff 6-4-97 (See Revision Note at chapter heading for Env-Ws 300); ss by #8352, eff 5-14-05 (formerly part of Env-Ws 380.22 )