What is the ideal pH for a swimming pool?

7.2 to 7.8. This range ensures bather comfort and maximizes the effectiveness of chlorine as a disinfectant (Table 2).

What is the required free chlorine level?

A minimum of 1.0 mg/l and a maximum of 3.0 mg/l (Table 2).

How often should pool water be tested?

For public pools, pH and free chlorine must be tested at least twice a day. Other parameters like Total Alkalinity and combined chlorine are tested less frequently, as specified in Annex A.

What is the maximum allowable turbidity?

The turbidity should not exceed 0.5 NTU (Nephelometric Turbidity Units) to ensure water clarity and safety (Table 1).

Are bacteria like E. coli allowed in pool water?

No, E. coli must be absent in a 100 ml sample of water, indicating no recent faecal contamination (Table 3).

IS 17260

: 2018

Specification for Water Quality of Swimming Pools and Similar Amenities

CurrentFrequently UsedSpecificationBIMMEP · Swimming Pools and Sports Facilities

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This standard specifies the requirements for water quality in swimming pools, spas, and similar recreational water amenities. It covers essential physical, chemical, and microbiological parameters to ensure the water is safe, hygienic, and aesthetically pleasing. The code also provides guidelines on disinfection methods and testing frequencies.

Specifies requirements for the physical, chemical, and microbiological quality of water in swimming pools and similar facilities.

Quick Reference Values

Acceptable pH Range7.2 to 7.8

Free Residual Chlorine1.0 to 3.0 mg/l

Combined Chlorine (Chloramines) Max0.5 mg/l

Turbidity Max0.5 NTU

Total Alkalinity80 to 120 mg/l

Cyanuric Acid (for outdoor pools) Max100 mg/l

Total Dissolved Solids (TDS) Max above fill water1500 mg/l

Practical Notes

Maintaining Total Alkalinity (TA) between 80-120 mg/l is crucial as it acts as a pH buffer, preventing rapid and large swings in pH levels.

For outdoor pools, Cyanuric Acid (stabilizer) is essential to prevent chlorine degradation from UV sunlight, but its concentration must be kept below 100 mg/l to avoid 'chlorine lock', where disinfection effectiveness is reduced.

Periodic 'shock dosing' (super-chlorination) is necessary to break down chloramines (combined chlorine), which are responsible for the 'chlorine smell' and eye irritation.