(1) Water chemistry, temperature, and clarity measurements must fall within the parameters set forth in Table 6:

 

Table 6.

 

Parameter	Acceptable range	Ideal range	Maximum
Chlorine	2-8ppm	3-5ppm	8ppm
Combined chlorine	0 to 0.5ppm	0.0	0.5ppm
Bromine	2-10ppm	2-8ppm	10ppm
Total Alkalinity	60-220ppm (varies by chemical type and pool surface)	80-100ppm for Cal Hypo, lithium hypo, and sodium hypochlorite; 100-120ppm for Sodium dichlor, trichlor, chlorine gas and bromine compounds	220ppm
Oxygen Reduction Potential (ORP or HRR, which stands for High Resolution Reduction)	650 minimum millivolts (mV)	650-750 minimum millivolts (mV)	no maximum
pH	7.2-7.8	7.4-7.6	7.2-7.8 for all pools, spas, or other water features except flow through hot springs, which may have a pH up to 9.4
Cyanuric Acid (allowed only in outdoor pools)	0-100ppm	10-50ppm	100ppm
Calcium Hardness	Pools 150-1,000ppm	Pools 200-400ppm; Spas 150-250ppm	Pools 1,000ppm Spas 800ppm
Temperature	Varies	Varies	Spas 104ºF Pools 100ºF EXCEPTION: flow through hot spring pools and spas, which may have a maximum temperature of 100ºF and 106ºF
Clarity	In the deepest part of the pool, spa, or other water feature, the main drain shall be clearly visible and sharply defined. NTUs must be in the range of 0.0-1.0	In the deepest part of the pool, spa, or other water feature, the main drain shall be clearly visible and sharply defined. NTUs must be less than .5	NTUs up to 1.0

 

(2) If total alkalinity is too low, it will result in pH bounce and a tendency to cause corrosion. If total alkalinity is too high, it will result in cloudy water increased scaling potential and a tendency for pH to be too high.

(3) Whenever isocyanurates or cyanuric acid (CYA) are used in a pool, spa, or other water feature, the concentrations of CYA shall not exceed 50 ppm. Recommended levels of CYA are 25-30 ppm. After March 1, 2010, isocyanurates or cyanuric acid shall not be used in newly constructed or renovated indoor pools, indoor spas, or other indoor water features or when a chlorinator is replaced. Licenseholders of indoor pools, spas, or other water features currently using isocyanurates or cyanuric acid shall have one year from March 1, 2010 to convert to a nonstabilized type of disinfectant.