Commercial pool filtration installation: UK standards and best practice
Is the existing swimming pool filter for your commercial facility letting you down? Whether you’ve received customer complaints about the water quality or want to spend less time and money with a more automated filtration system, talk to our team today.
We can help you to not only meet the UK standards and best practices for commercial pool filtration, but exceed them – highlighting the premium services of your health club, gym, hotel, spa, school, or sports and leisure centre to all visitors.
Key regulations and standards
While there are no regulations specifically relating to commercial pool filtration in the UK, these systems must abide by general Health and Safety Executive (HSE) legislation (as per the Health and Safety at Work etc. Act 1974 and the associated regulations), with the Pool Water Treatment Advisory Group (PWTAG) standards considered best practice.
With regards to HSE legislation which applies to pools used by the public for water-related activities, the focus is on ensuring the water is safe and hygienic through regular inspections, staff training, and the implementation of emergency procedures.
PWTAG standards, on the other hand, provide clearer, more specific guidance with regards to the recommended pool filtration duties of commercial pool and spa managers, such as maintaining levels of disinfectant, safely disposing of backwash water, and ensuring the optimum level of filtration is being used.
According to PWTAG guidance, some of the most essential components of maintaining a safe commercial pool filtration system include:
Water disinfection and pH balance
While the recommended chlorine levels vary depending on pool type and bathing load, standard public swimming pools should maintain chlorine levels between 1.0 and 3.0 mg/L and a pH level of between 7.2 and 7.4.
Filtration rate
For public swimming pools with high bathing loads, medium-rate filtration is often recommended, operating up to 25m3/m2/h (or 25m/h). However, opting for a higher-rate pool filter can deliver superior filtration results.
Filter type
PWTAG advises that high-rate granular media filters (sand filters) are the preferred filter type for commercial pools, with graded sand or approved glass media being recommended. In some cases, regenerative media is also acceptable for more modern commercial swimming pools, but its suitability must be proven.
Conversely, cartridge and Diatomaceous Earth (DE) filters are not recommended for this purpose by PWTAG as they’re typically better suited to domestic applications.
Turnover time
For a standard public pool, the recommended turnover time (the time in which the entire volume of water in the pool has passed through the filtration system) is 2.5 to 3 hours. PWTAG also offers guidance on pool shape and size, materials and finishes, and even lighting.
Disposing of backwash water
To prevent pollution and protect swimmers, backwash water expelled from the pool filter should be properly disposed of via a public foul (sanitary) sewer. In some cases, pool managers may need to seek consent or permits for a backwash water disposal route from their local authority.
Monitoring water quality
To ensure safe and hygienic swimming conditions, regular water quality monitoring is essential. While chlorine and pH levels should be tested three times a day, water temperature requires daily testing, and alkalinity and microbiological testing should be carried out weekly.
According to PWTAG, the level of calcium hardness and total dissolved solids (TDS) should also be checked once a month.
Logging and record keeping
From chlorine water tests to backwashing and carrying out other routine maintenance procedures, every activity relating to the upkeep of the pool should be accurately recorded in a logbook or digital system.
This process not only helps to demonstrate health and safety compliance but can also be crucial for identifying and rectifying any issues.
Pool design and surveying
Getting the design of your commercial pool right from the start can help to reduce future filtration problems. At this survey and design stage, for example, pool managers should consider the creation of an easily accessible pool plant room that allows for regular maintenance.
They should also have a clear understanding of hydraulic design principles to help prevent ‘dead zones’ where water circulation is poor, and the filtration system should also be designed in accordance with the pool’s flow rate, bather load, and turnover period.
BMS (building management system) and automation integration
PWTAG understands and outlines the importance of automated controls for pool filtration purposes in its Code of Practice (2021). Saving a substantial amount of time and manual input, these systems can handle disinfectant dosing, monitoring chemicals, regulating pH levels, controlling pool temperature, and initiating backwash cycles.
Where possible, PWTAG recommends linking dosing systems to continuous monitoring equipment, allowing them to make real-time adjustments. Despite the automated system, manual tests should also be conducted daily to ensure accuracy is within acceptable limits and if not, check whether recalibration is needed.
When carrying out calibration maintenance of an automatic system, manufacturers' recommendations should be followed, and accurate records of the tests and their results should be kept. Staff members must be provided with the necessary documentation and training to support with calibration and troubleshooting requirements.
These automated systems should also feature fail-safe mechanisms that shut off automated dosing pumps in the event of circulation system failure, helping to prevent chemical overdosing.
If possible, integrating the automated system into a BMS is recommended to allow for centralised remote monitoring and control, faster fault detection, and greater energy efficiency.
Case study: White House Spa, Indoor Pool
At Chemsol Group, our professional team has used their extensive pool filtration expertise to design and build countless commercial pool plant rooms across the UK, including one such facility at the White House Spa in Rhuallt, Wales.
To help the award-winning spa and health club achieve superior water filtration and boost their guest satisfaction, Chemsol installed the first swimming pool plant room Da-Gen Daisy+ filtration system in a commercial setting in the UK.
This innovative system uses a revolutionary filter media made from green glass known as AFM (Activated Filter Media) as a direct replacement for quartz sand, delivering the sought-after benefits of reduced maintenance needs as well as enhanced water quality.
The result — A 12-metre luxury indoor swimming pool and heated outdoor hydrotherapy pool with massage jets where the water is filtered down to 1 micron (a fraction of sand's typical 20-micron limit), ensuring clearer, purer, and safer water for your guests.
Schedule a free site survey by Chemsol
Transform your commercial pool into the area’s premier leisure destination. Ready to explore smarter, more efficient filtration solutions? Simply schedule your free site survey, our pool specialists will visit at a time that suits you, walk you through our detailed analysis, and recommend the ideal pool filtration system for your facility.
Beyond design and installation of your commercial pool plant room, Chemsol Group offers flexible service plans—including routine maintenance and emergency repairs to ensure uninterrupted operation during business hours.
Speak with our team today on 01492 582 888, email info@chemsol.co.uk, or use our online contact form to discover the perfect filtration system for your pool or spa.