Section 410IAC6-2.1-30. Pool water chemistry

   (a) All pools, when open for use, shall be continuously and automatically disinfected with a chemical that imparts an easily measured, free residual.

  (b) A free residual of the disinfectant chemical shall be maintained throughout the pool at concentrations in accordance with the following:

	CHLORINE		BROMINE
POOL TYPE	Minimum	Maximum	Minimum	Maximum
Wading pools	3.0 ppm	7.0 ppm	4.0 ppm	10.0 ppm
Spa pools	2.0 ppm	7.0 ppm	4.0 ppm	10.0 ppm
Waterslide plunge pools	2.0 ppm	7.0 ppm	3.0 ppm	10.0 ppm
Wave pools	2.0 ppm	7.0 ppm	3.0 ppm	10.0 ppm
All other pools	1.0 ppm	7.0 ppm	2.0 ppm	10.0 ppm

  (c) Whenever the residual disinfectant:

(1) falls below the minimum concentration required; or

(2) exceeds the maximum concentration allowed;

the pool shall be cleared and kept free of bathers until disinfectant residuals are within the acceptable range.

  (d) The department may accept other disinfecting materials or methods when the materials or methods have been demonstrated:

(1) to provide a residual effect equivalent to halogens;

(2) to be easily measured under conditions of use;

(3) not to be dangerous to public health;

(4) not to create objectionable physiological effects; or

(5) not to impart toxic properties to the water.

  (e) The pool water shall be superchlorinated to breakpoint or superoxidized with a nonchlorine oxidizer when the pool test kit reveals a combined chlorine (chloramine) concentration of five-tenths (0.5) parts per million (ppm) or greater.

  (f) Chlorinated isocyanurates or stabilized chlorine shall not be used for breakpoint chlorination.

  (g) The pool shall be closed and remain closed during breakpoint chlorination until the chlorine concentration drops to the maximum level referenced in subsection (b).

  (h) If a nonchlorine oxidizer is used to superoxidize, the pool shall be closed and shall remain closed in accordance with the specifications on the product label.

  (i) A test kit shall be readily available for use by the pool operator, with reagents replaced according to manufacturer's requirements, and meet the following:

(1) For pools that use chlorine as a disinfectant, a test kit shall be used that covers a minimum range of zero (0.0) ppm to five (5.0) ppm or higher. The test kit must be:

(A) in increments of five-tenths (0.5) ppm; and

(B) capable of measuring total chlorine.

(2) Orthotolidine may not be used as the disinfectant testing reagent.

(3) For pools that use a disinfectant other than chlorine, the test kit shall have the range and accuracy proportionate to the range required for chlorine test kits.

(4) A pH test kit:

(A) accurate to the nearest two-tenths (0.2) pH unit; and

(B) covering a minimum range of seven (7.0) to eight (8.0) pH units;

shall be used.

(5) When a cyanurate is used as a chlorine stabilizer, the test kit shall be capable of measuring cyanuric acid concentrations.

(6) A test kit capable of measuring total alkalinity shall be used.

  (j) If chlorinated isocyanurate or cyanuric acid stabilizers are used in a pool, the concentration shall not exceed sixty (60) ppm. When the maximum allowable cyanuric acid concentration is exceeded, the pool must be closed until appropriate measures are taken to lower the concentrations to the required range.

  (k) Chlorinated isocyanurates and cyanuric acid stabilizers shall not be used in any indoor pool.

  (l) Only in pools where chlorine is used as the disinfectant can cyanuric acid be used as a stabilizer.

  (m) The water in a pool shall have a pH of not less than seven and two-tenths (7.2) and not more than seven and eight-tenths (7.8).

  (n) The alkalinity of the water in pools shall be at least eighty (80) ppm and no more than one hundred twenty (120) ppm as titrated to the methyl orange endpoint unless it can be shown that another level of total alkalinity produces chemically balanced water based on calculations approved by the department.

  (o) Pool water shall be tested for the following:

(1) pH and disinfectant residuals daily before the pool is open for use and at least one (1) other time during the hours of pool use.

(2) Combined chlorine at least twice a week when chlorine is used.

(3) Total alkalinity at least once a week.

(4) Cyanuric acid, when it is used, at least once a week.

  (p) Spa water shall be tested for pH and disinfectant residuals daily before the spa is open for use and at least two (2) other times during the hours of spa use for the following:

(1) Combined chlorine concentration, when chlorine is used, at least twice a week.

(2) Total alkalinity at least once a week.

  (q) All results shall be recorded.

  (r) If electronic monitoring devices are used, the accuracy of the device must be checked as required by the manufacturer or compared for accuracy at least once per week with a test kit. Use of oxidation reduction potential (ORP) controllers does not negate the manual daily testing requirement for disinfectant residuals.

  (s) The pool shall be closed for at least one (1) hour following the manual addition of a chemical directly to the pool water.

  (t) Any chemical used to treat the water in a pool must be used in accordance with the product label directions. (Indiana State Department of Health; 410 IAC 6-2.1-30; filed May 19, 2003, 8:30 a.m.: 26 IR 3328; readopted filed Jul 8, 2009, 1:44 p.m.: 20090805-IR-410090209RFA; filed Jul 26, 2010, 2:16 p.m.: 20100825-IR-410090006FRA; readopted filed Sep 30, 2015, 2:45 p.m.: 20151028-IR-410150169RFA)