R392-302-27. Disinfection and Quality of Water  


Latest version.
  •   (1) Disinfection Process.

      (a) A pool must be continuously disinfected by a product which:

      (i) Is registered with the United States Environmental Protection Agency as a disinfecting process or disinfectant product for water;

      (ii) Imparts a disinfectant residual which may be easily and accurately measured by a field test procedure appropriate to the disinfectant in use;

      (iii) Is compatible for use with other chemicals normally used in pool water treatment;

      (iv) Does not create harmful or deleterious effects on bathers if used according to manufacturer's specifications; and

      (v) Does not create an undue safety hazard if handled, stored and used according to manufacturer's specifications.

      (b) The concentration levels of the active disinfectant within the pool water shall be consistent with the label instructions of the disinfectant and with the minimum levels listed in Table 6 for all circumstances, bather loads, and the pH level of the water.

      (i) At no time shall the concentration level of free available chlorine reach a level above ten parts per million while the facility is open to bathers.

      (2) Products used to treat or condition pool water shall be used according to the product label.

      (3) Testing Kits.

      (a) An easy to operate pool-side disinfectant testing kit, compatible with the disinfectant in use and accurate to within 0.5 milligrams per liter, must be provided at each pool.

      (b) If chlorine is the disinfectant used, it must be tested by the diethyl-p-phenylene diamine method, the leuco crystal violet method, or another test method approved by the Department.

      (c) If cyanuric acid or stabilized chlorine is used, a testing kit for cyanuric acid, accurate to within 10.0 milligrams per liter must be provided.

      (d) Expired test kit reagents may not be used.

      (4) Chemical Quality of Water.

      (a) If cyanuric acid is used to stabilize the free residual chlorine, or if one of the chlorinated isocyanurate compounds is used as the disinfecting chemical, the concentration of cyanuric acid in the water must be at least ten milligrams per liter, but may not exceed 100 milligrams per liter.

      (b) The difference between the total chlorine and the free chlorine in a pool shall not be greater than 0.5 milligrams per liter. If the concentration of combined residual chlorine is greater than 0.5 milligrams per liter the operator shall breakpoint chlorinate the pool water to reduce the concentration of combined chlorine.

      (c) Total dissolved solids shall not exceed 1,500 milligrams per liter over the startup total dissolved solids of the pool water.

      (d) Total alkalinity must be within the range from 100 to 125 milligrams per liter for a plaster lined pool, 80 to 150 milligrams per liter for a spa pool lined with plaster, and 125 to 150 milligrams per liter for a pool lined with other approved construction materials.

      (e) A calcium hardness of at least 200 milligrams per liter must be maintained.

      (f) The saturation index value of the pool water must be within the range of positive 0.3 and minus 0.3. The saturation index shall be calculated in accordance with Table 5.

      (5) Water Clarity and Temperature.

      (a) The water must have sufficient clarity at all times that the drain grates or covers in the deepest part of the pool are readily visible. As an alternative test for clarity, a black disk, six inches in diameter, must be readily visible if placed on a white field in the deepest part of the pool.

      (b) Pool water temperatures for general use should be within the range of 82 degrees Fahrenheit, 28 degrees Celsius, to 86 degrees Fahrenheit, 30 degrees Celsius.

      (c) The minimum water temperature for a pool is 78 degrees Fahrenheit, 26 degrees Celsius.

      (d) The local health department may grant exemption to the pool water temperature requirements for a special purpose pool including a cold plunge pool, but may not exempt maximum hot water temperatures for a spa pool.


    TABLE 5


    CHEMICAL VALUES AND FORMULA FOR CALCULATING SATURATION INDEX


    The formula for calculating the saturation

    index is:

    SI = pH + TF + CF + AF - TDSF

    SI means saturation index

    TF means temperature factor

    CF means calcium factor

    mg/l means milligrams per liter

    deg F means degrees Fahrenheit

    AF means alkalinity factor

    TDSF means total dissolved solids factor.


    Temperature Calcium Hardness Total Alkalinity

    deg. F TF mg/l CF mg/l AF


    32 0.0 25 1.0 25 1.4

    37 0.1 50 1.3 50 1.7

    46 0.2 75 1.5 75 1.9

    53 0.3 100 1.6 100 2.0

    60 0.4 125 1.7 125 2.1

    66 0.5 150 1.8 150 2.2

    76 0.6 200 1.9 200 2.3

    84 0.7 250 2.0 250 2.4

    94 0.8 300 2.1 300 2.5

    105 0.9 400 2.2 400 2.6

    128 1.0 800 2.5 800 2.9


    Total Dissolved Solids


    mg/l TDSF


    0 to 999 12.1

    1000 to 1999 12.2

    2000 to 2999 12.3

    3000 to 3999 12.4

    4000 to 4999 12.5

    5000 to 5999 12.55

    6000 to 6999 12.6

    7000 to 7999 12.65

    each additional 1000, add .05


    If the SATURATION INDEX is 0, the water is chemically in

    balance.

    If the INDEX is a minus value, corrosive tendencies are

    indicated.

    If the INDEX is a positive value, scale-forming tendencies

    are indicated.

    EXAMPLE: Assume the following factors:

    pH 7.5; temperature 80 degrees F, 19 degrees C;

    calcium hardness 235; total alkalinity 100; and total dissolved solids 999.

    pH = 7.5

    TF = 0.7

    CF = 1.9

    AF = 2.0

    TDSF = 12.1

    TOTAL: 7.5 + 0.7 + 1.9 + 2.0 - 12.1 = 0.0

    This water is balanced.



    TABLE 6


    DISINFECTANT LEVELS AND CHEMICAL PARAMETERS


                               POOLS SPAS SPECIAL

                                                        PURPOSE


    Stabilized Chlorine(2)

       (milligrams per liter)

       pH 7.2 to 7.6 2.0(1) 3.0(1) 2.0(1)

       pH 7.7 to 8.0 3.0(1) 5.0(1) 3.0(1)

    Non-Stabilized Chlorine(2)

       (milligrams per liter)

       pH 7.2 to 7.6 1.0(1) 2.0(1) 2.0(1)

       pH 7.7 to 8.0 2.0(1) 3.0(1) 3.0(1)

    Bromine 4.0(1) 4.0(1) 4.0(1)

       (milligrams per liter)

    Iodine 1.0(1) 1.0(1) 1.0(1)

       (milligrams per liter)Ultraviolet and Hydrogen 40.0(1) 40.0(1) 40.0(1)

       Peroxide

       (milligrams per liter

       hydrogen peroxide)

    pH 7.2 to 7.8 7.2 to 7.8 7.2 to 7.8

    Total Dissolved 1,500 1,500 1,500

       Solids (TDS)

       over start-up

       TDS

       (milligrams per liter)

    Cyanuric Acid 10 to 100 10 to 100 10 to 100

       (milligrams per liter)

    Maximum Temperature 104 104 104

       (degrees Fahrenheit)

    Calcium Hardness 200(1) 200(1) 200(1)

       (milligrams per liter as calcium carbonate)

    Total Alkalinity

       (milligrams per liter as calcium carbonate)

       Plaster Pools 100 to 125 80 to 150 100 to 125

       Painted or Fiberglass 125 to 150 80 to 150 125 to 150

       Pools

    Saturation Index Plus or Plus or Plus or

      (see Table 5) Minus 0.3 Minus 0.3 Minus 0.3

    Chloramines 0.5 0.5 0.5

      (combined chlorine

      residual, milligrams

      per liter)


    Note (1): Minimum Value

    Note (2): Maximum value of free chlorine is ten milligrams per

    liter as stated in Subsection 27(1)(b)(i).


      (6) Pool Water Sampling and Testing.

      (a) At the direction of the Local Health Officer, the pool operator or a representative of the local health department shall collect a pool water sample from each public pool at least once per month or at a more frequent interval as determined by the Local health Officer. A seasonal public pool during the off season and any public pool while it is temporarily closed, if the pool is closed for an interval exceeding half of that particular month, are exempt from the requirement for monthly sampling. The operator or local health department representative shall submit the pool water sample to a laboratory approved under R444-14 to perform total coliform and heterotrophic plate count testing.

      (b) The operator or local health department shall have the laboratory analyze the sample for total coliform and heterotrophic plate count using methods allowed under R444-14-4.

      (c) If the operator submits the sample as required by local health department, the operator shall require the laboratory to report sample results within five working days to the local health department and operator.

      (d) A pool water sample fails bacteriological quality standards if it:

      (i) Contains more than 200 bacteria per milliliter, as determined by the heterotrophic plate count or

      (ii) Shows a positive test for presence of coliform or contains more than 1.0 coliform organisms per 100 milliliters.

      (e) Not more than 1 of 5 samples may fail bacteriological quality standards. Failure of any bacteriological water quality sample shall require submission of a second sample within one lab receiving day after the sample report has been received.