(1) An approved test kit for determining the pH range of 6.8 to 8.2, or 7.2 to 8.5 for hot springs pools, must be provided. The kits must be capable of measuring pH accurately to the nearest 0.2 pH units.

(2) A test kit for the determination of total alkalinity shall be provided.

(3) An approved test kit or oxidation reduction potential (ORP) measuring device for the determination of chlorine residuals in the range of 0 to 5.0 parts per million, or bromine residuals in the range of 0 to 8.0 parts per million, must be provided. When testing kits for chlorine utilize comparative color standards, the standards must be accurate to within plus or minus 0.1 ppm. The test kit must test for free and total chlorine residual. DPD test method is the required procedure.

(4) Whenever cyanurates are used as a stabilizer, a test kit shall be provided which is capable of accurately measuring the cyanurate concentration to 150 parts per million in increments of 25 parts per million. Cyanurate concentrations in the pool or spa shall not be higher than 150 parts per million.

(5) Equivalent test kits or ORP measuring devices for other approved disinfectant residuals must be provided.

(6) ORP may be used as an additional diagnostic tool to aid in the determination of overall water quality but must not be used as a complete substitute for DPD testing. If ORP is used as an additional diagnostic tool for determining sanitizer strength, the minimum standard is 650 millivolts (mV) and the preferred standard is 750 mV.