ABOUT THE CLIENT - SWIMMING POOL IN ENGLAND

The Repton Prep is a prestigious school based in Derby, having a 6-lane swimming pool available for school, club, and public use.

Working closely with the company FT Leisure, one of the UK’s leading innovative engineering solutions and service companies to UK public swimming pools, a comprehensive upgrade of the swimming pool was carried out.

The upgrade included a complete overhaul of the pool plant room utilizing state-of-the-art equipment, to improve the health and well-being of the swimmers using the pool. This included the installation of a new state-of-the-art medium-pressure UV system to support the new filtration and associated pool equipment.

WHAT THE CLIENT NEEDED - IMPROVED BATHER QUALITY & SAFETY

Being able to guarantee an upgrade in bather safety and water quality improvement was essential. Additionally, the UV system was required to be easy to operate for Repton’s onsite maintenance team, as well as to be operationally robust and as maintenance-free as possible, to reduce any unnecessary support calls to the new site.

The usage pattern of the pool required a robust system that would provide a secondary disinfection barrier and at the same time provide a verified and targeted approach to reducing chloramines. Chloramines are disinfection by-products created when bathers release nitrogenous-based organics into the water. Chloramines create the unpleasant smell that is associated with red eye issues for bathers and are linked to potential long-term health issues.

THE SOLUTION - UV SYSTEM FOR MINIMIZED COMBINED CHLORINE LEVELS

The UV system selected for living up to the defined conditions was a MULTIRAY DN150 MP1-3500, using an optimized 3.5 kW medium-pressure lamp. The system was selected to provide treatment at a maximum flow rate of 92m3/h using a dose of 60 mj/2 at 94% UVT.

The MULTIRAY series is solely optimized for pools, as it utilizes 254nm dose calculations for the disinfection of chlorine-resistant pathogens such as Cryptosporidium & Giardia. The scientifically optimized polychromatic lamp also has been developed to emit a spectral output at the peak absorbed levels of chloramines.  This allows the MULTIRAY series to reduce chloramines in pools much more efficiently and without absorbing as much free chlorine as a standard medium-pressure lamp might do. This reduces the operators’ costs and pool management time as operators do not have to compensate for the UV to the same degree to ensure the facility’s pool chemistry is maintained.

The service and maintenance manager at Repton stated that they have rarely seen combined chlorine levels higher than 02.ppm throughout the last year and that they have been extremely happy with the UV system, as no critical faults have occurred in over 10.000 hours of operation.

UV design information:

• Flow Rate of 92 m3/h
• UV Transmission of 94%
• UV Dose of 60 mJ/2