Industry Applications
Important note: UV disinfection for swimming pools works as an auxiliary disinfection method. It cannot completely replace chlorine‑based disinfectants. Residual chlorine in water shall be maintained to meet sanitary standards. According to Chinese standard CJJ122‑2017, the UV dose shall be ≥60 mJ/cm² for indoor pools and ≥40 mJ/cm² for outdoor pools. Full‑flow treatment is required. Install the unit after filters and before heating equipment. A bypass pipeline shall be equipped for maintenance.
Calculate the maximum system circulation flow according to pool circulation cycle. The rated flow of UV equipment shall be no less than system circulation flow, with 10‑20 % safety margin. Increase the margin further when water temperature is above 25 °C.
For indoor public pools, target for chloramine decomposition. Maintain UV dose ≥60 mJ/cm². Outdoor pools start from ≥40 mJ/cm².
Influent turbidity shall be controlled ≤1 NTU. High turbidity reduces UV transmittance significantly. Adequate pre‑filtration is essential.
| Type | Features | Applicable Pool Scenarios |
|---|---|---|
| Low‑pressure UV | Single wavelength at 254 nm, high electro‑optical efficiency, low power consumption. Hardly decompose chloramines. Suitable for frequent start‑stop. Lamp service life: 8000‑10000 h. | Private residential pools. For disinfection only, no requirement for chloramine removal. Budget‑oriented projects. |
| Medium‑pressure UV | Broad‑spectrum 200‑400 nm. Effective for chloramine decomposition and chlorine odor elimination. Inactivate chlorine‑resistant microorganisms such as cryptosporidium. High single‑lamp power, compact footprint. Higher energy consumption and higher procurement cost. Lamp service life: 6000‑9000 h. | Indoor public pools, club pools, competition pools. High bather load, chloramine removal required. Recommended for public indoor pool projects. |
Remark: Medium‑pressure UV is preferred for domestic public indoor swimming pool projects per local code.
Chamber material: 316L stainless steel is preferred for chlorine‑containing pool water. 304 stainless steel is acceptable for small private pools. Mirror‑polished inner surface with UV reflectivity ≥85 % to improve disinfection performance.
Quartz sleeve: High‑transmittance quartz with transmittance ≥90 %, pressure resistance ≥0.6 MPa.
Cleaning mechanism: Automatic mechanical cleaning is strongly recommended for public pools. Manual cleaning is acceptable for small private pools. Scale buildup on quartz sleeves will drastically degrade UV performance.
Control system: Equipped with UV intensity sensor and flow switch. Auto lamp cut‑off under no‑flow condition to avoid dry‑burning. Alarm function and operation data logging are preferred.
Sanitary approval for water‑related products and disinfection manufacturer certificates, mandatory for public project acceptance.
Verify target UV dose at rated flow rate, instead of only checking lamp wattage.
Safety filter at outlet is suggested to prevent quartz fragments from entering pool water.
Installation position: After filter, before heat exchanger / heater. Bypass pipeline is required for maintenance without pool shutdown.
Water flow direction shall be parallel with UV lamps to guarantee sufficient exposure time. Reserve space for lamp replacement and service.
Multiple units shall be installed in parallel instead of series connection.
Residential private pool: Low‑pressure UV, match circulation flow, manual cleaning, work together with chlorine disinfection.
Indoor public / club pool: Medium‑pressure UV, dose ≥60 mJ/cm², automatic cleaning, UV intensity monitoring, full‑flow treatment, keep residual chlorine.
Outdoor pool: Either low‑pressure or medium‑pressure UV acceptable, dose ≥40 mJ/cm². Pay attention to sun protection and temperature‑related safety margin.
