What is the Code of Practice? The PWTAG Code of Practice provides pool operators with a structured plan for the technical operation of their pool. The code ensures that the technical operation of a pool meets quality standards that provide a healthy experience for swimmers using recognised and established practices, techniques, engineering and design. For this reason, all UK pools are encouraged to follow it.
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The Code provides a model of operation based on the authority of PWTAG good practice. Following the Code gives an assurance to operators and to the public that the pool meets essential healthy pool operational standards. The Code is designed, among other things, to meet the health challenge of one of the greatest threats that the sector has to deal with - the chlorine-resistant pathogen. The code is based on the 2009 PWTAG book, Swimming Pool Water: treatment and quality standards for pools and spas. It does not replace the book. Operators should still refer to it, and it provides some of the basics for PWTAG's training material. Pools that follow the Code of Practice can put themselves forward to be assessed against it.
Pools that meet the standard of the Code can be recognised by accreditation with the PWTAG Poolmark award. This CoP contains general operational and safety recommendations for the management of swimming pool water treatment systems and associated water treatment plant, heating and ventilation systems. The CoP sets out how the technical operation of the pool should function for a safe and successful swimming pool water. Updated to reflect the requirements of Managing Health and Safety in Swimming Pools (HSG179) 1.1) Why a code of practice? The purpose of this CoP is to provide pool managers and operators with the fundamental principles of good practice in swimming pool water technical operation. Following it, pool staff should be able to provide a safe, enjoyable swimming experience for users as well as a safe operation for workers.
1.2) The main risk in swimming pool water treatment are health issues. Water quality. Chemical risks. Physical risks (e.g. Drowning, slips and trips, entrapment). Infection (e.g. The pool operator has a general duty to set out a safety policy for the operation of the pool in its environment.
2.1) PSOP - Pool safety operational procedures The recognised way to define a pool’s safety policy is to establish and maintain pool safety operational procedures (PSOP). There should be two sections – normal operational plans (NOP) and emergency action plans (EAP). The PSOP should include management’s assessment of hazards associated with all aspects of the pool – physical, risk of infections and supervisory – as well as a section on the technical operation of the pool which features swimming pool water quality. 2.2) Pool technical operation procedures (PTOP) This CoP requires pool management to define and document its policy and procedures for the general operation of the pool water treatment.
This is called the pool technical operation procedures (PTOP). The PTOP forms a part of the risk assessment process for the whole pool facility and the subsequent formulation of pool safety operational procedures (PSOP).
It should take the form of a stand-alone document detailing a swimming pool’s technical operation which is part of the PSOP. The pool PTOP will be based on PWTAG published guidance, but more particularly the requirements of the suppliers, manufacturers and installers of plant and equipment. It will set out how the plant should function and be operated safely. Just as significantly, the PTOP for a pool will incorporate operational considerations that provide a healthy, enjoyable, satisfying and safe experience for users. The PTOP may use this CoP for its structure, supplemented or amended where appropriate to the individual circumstances of a pool.
2.3) Planning and organising Preparing a PTOP demands planning the approach to pool water, ensuring that it integrates with other management activities. 2.4) Elements of an organisation’s PTOP Whatever the size of organisation and resources available, the first step is to establish a policy for water quality, safety, and hygiene and to have a strategy for its implementation.
There should be clear objectives and a good management plan to achieve them. Learning from experience is important. You should review the outcomes and, if necessary, make changes to improve things. Preparing a PTOP is no different to other management processes that demand a systematic approach, as shown in the diagram below.
2.5) Policy and planning Developing a policy for water quality management and promoting a plan for its achievement will ensure effective use of the organisations' resources as well as ensuring bather safety. An effective policy will:. Demonstrate the commitment of senior management to the quality and safety of pool water. Integrate the quality and safety of pool water management with other relevant organisational policies and management activities throughout the organisation. An effective strategy will:. Clearly set out how the organisation is structured to deal with the quality and safety of pool water issues. Show how that organisation might usefully change, and set out the steps to get there.
Identify the resources, in money and staff time, necessary to achieve the objectives. 2.6) Planning and organising Develop plans for the management of the quality and safety of pool water at levels appropriate to the size and structure of the organisation. A large enterprise attracting hundreds of thousands of bathers each year would need a detailed PTOP. For a small pool, open on a limited basis, a much more basic document covering essentials would be sufficient. This code of practice contains the information necessary for producing such a document.
2.7) Implementation and operation The key to implementation and operation is defining clear roles and maintaining the awareness of those involved. Define clear roles - State who is responsible for carrying out each task identified in the PTOP. Awareness - Pool management should establish and maintain procedures in the PTOP to make staff and others involved aware of the importance of their roles and responsibilities in complying with the pool procedures, and with the requirements of the PTOP. Performance monitoring - There should be a programme of inspection and clear records kept of the findings and actions. It helps to follow a written programme of priorities, keeping a record of what has been done, when, where and by whom, then listing work planned for the future. Management will then be able to demonstrate progress and ensure that the investigation and resolution of any outstanding issues is included in a work programme. Learn from incidents and near misses - Incident and accident data are valuable indicators of risk and provide a measure of performance.
Near misses should not be ignored; rather, staff should be encouraged to report them and treat them as an opportunity to learn from something that did not quite happen, this time. The effective technical operation and safety in any swimming pool starts with careful planning, specification and design.
The specific sources of information from which the technical design and planning standards recommended for swimming pools can be obtained are:. BS EN standards 15288-1 Safety requirements for design. BS EN standards 15288-2 Safety requirements for operation.
PWTAG Swimming Pool Water: treatment and quality standards for pools and spas. PWTAG online Technical notes.
Sport England Swimming Pools Design Guidance Note. Everyone involved in the process of specifying, designing and constructing pools should be familiar with these design standards and should ensure that they are given careful consideration in all pool projects. Water treatment systems are an integral part of the architectural, structural and mechanical design of a swimming pool. The design, selection and operation of water treatment plant has to take into account:. Public health hazards. Mains water quality and storage, dilution and drainage, coagulation, filtration and disinfection. The size and type of pool, bathing load, circulation rate, circulation hydraulics and turnover period.
Pool operation, water treatment system and plant room. 3.1) Public health hazards Within a pool facility there are many potential uses of water where users and those in the vicinity may be exposed to hazards with the potential to cause injury and waterborne illness. Examples include:. Death through drowning, including hair and limb entrapment. Neck and head injuries from diving into shallow water or hitting other swimmers. Injury from falls, slipping, etc.
Potential drowning where cloudy water prevents surveillance of swimmers under the water. Cuts and abrasions due to sharp edges, cracked tiles etc. Ingestion of pool water containing pathogens (microorganisms causing illness) including the protozoal parasites Cryptosporidium and Giardia that can cause gastroenteritis. Contact with contaminated water, especially in contact with open wounds. Inhalation of aerosols containing hazards e.g.
Pool water should circulate 24 hours a day. If the pool has a moveable floor or bulkhead (boom), the circulation system should ensure proper water distribution in all possible positions. 4.1) Surface water removal Surface water should be removed from swimming pools (a deck-level system is best). Between 50 and 80% (even 100% where the pool has bottom inlets) of the circulation flow should be removed as surface water. 4.2) Inlets and outlets Inlets and outlets, grilles and covers should be designed in accordance with BS EN 13451-3. They should be inspected visually every day, and once a month subject to closer examination for obstruction, impact damage and vandalism and to make sure that they are correctly in place. If they are damaged or missing, swimming should be suspended immediately.
Inlets: in water less than 800mm in depth and in sensitive areas (steps, teaching points, beside base inlets, etc.) the velocity of the water entering the pool should not exceed 0.5m/sec. In other areas, the velocity of the water entering the pool should not exceed 2.0m/sec. Outlets can cause entrapment and therefore have the capacity for serious harm. PWTAG guidance is that all pools should be tested to show that outlets comply with BS EN 13451-3. New completed pools should have this certification when built. Where this is not the case, pool outlets should be tested by a competent authority to show that they comply.
Outlets should also be tested for hair entrapment. Annex D describes a test for hair entrapment. Pool outlets should be designed and installed so as to reduce the potential for entrapment of the user. As a general requirement, water speed through the outlet grilles should be ≤0.5m/sec. Grilles in outlets and inlets should comply with the requirements of BS EN 13451-1 and have gaps no greater than 8mm to prevent entrapment hazards.
All wall and floor outlets should be fitted with a sump to a design that accords with BS EN 13451-3. 4.3) Where there is more than one outlet Outlet systems should be designed in such a way that:. There are at least two functioning suction outlets per suction line. The distance between the nearest points of the perimeters of the devices is ≥2m. If any one of the suction outlets becomes blocked, the flow through the remaining suction outlet/s shall accommodate 100% of the flow rate.
It is not possible to isolate one of the outlet sump suction lines by means of a valve. 4.4) One outlet In pools with only one outlet, the grille should be designed in such a way that:. It cannot be blocked. One user cannot cover more than 50% of the opening.
Raised grilles can be domed opposite to the flow direction, with prevalent peripheral suction; the height of the dome shall be at least 10% of the main dimension (diameter). Single grilles should have a grille area of ≥1m2. Effective filtration is the primary mechanism for ensuring water clarity. An effective filtration system including coagulation will also remove more than 90% of Cryptosporidium oocysts in a single pass of water-containing oocysts through the filter bed. It is an important function as these oocysts are much more resistant to disinfection than bacteria and viruses. This CoP specifies filtration standards in terms of medium-rate filters using granular filter media, typically sand. This is a tried and tested method.
There are filters that operate at higher rates, some with other media, some applying different filtration principles. These may be able to filter satisfactorily in some conditions, but operators should understand the potential disadvantages and be satisfied that they produce good clarity in the pool. Membrane and ultrafiltration systems are equally suitable and do not require the use of coagulant. There are many pools in the public sector, where bather loads are not as high or as critical as public community pools (e.g.
Health clubs, hotels, schools) that use high-rate filtration – over 25 and up to 50 metres per hour. High-rate filters do not filter as well as medium-rate filters. Tests have shown they are about 10 to 25% as effective as medium rate. Accordingly, in these situations the bather loading should reflect the relative inefficiency of these filters (given that turnover and circulation are similar to pools with medium rate filters). Their use should be subject to a risk assessment.
5.1) Filters and filtration rate Filters will usually be medium-rate pressure filters; 10 to 30m/h is the norm for public sector swimming pools with sand as the main filter medium (other filter media can be used). 5.2) Filter beds Filters may be either single or multi-grade type.
For single-grade filters the sand bed should be a minimum of 800mm deep; for multi-grade filters the sand bed should be a minimum 550mm deep supported on a bed of coarser material 250mm deep. 5.3) Serviceable filters Every filter should be designed to be serviceable. They should have:. An automatic air eliminator and a safe, manually operated quick air release mechanism. Differential pressure gauges to indicate the pressure at the filter inlet and outlet. A full-bore sight glass to observe the clarity of the effluent water throughout backwashing.
One or two viewing ports (acrylic windows) to observe the fluidisation of the bed during backwashing. Access manholes – the number and size to be as indicated by the Confined Spaces Regulations 1997.
For steel filters, and glass reinforced plastic (GRP) filters over 1.4m diameter, this means one manhole on the top and one on the side towards the bottom; each one at least 450mm diameter. An air scour system to aid backwashing will enhance the cleaning process.
5.4) Annual inspection The internal condition of the filters and the top of the filter media bed should be inspected annually for corrosion and problems with the filter medium e.g. Mud balling, fissures, uneven bed. 5.5) Backwashing. Medium rate filters should be backwashed at least once a week and whenever the pressure loss across the filter media bed reaches the level specified by the filter manufacturer. The backwashing period should continue either in accordance with the manufacturers’ specified time or until the backwash water is clear – whichever is the longer. Filters should also be backwashed if the water circulation has been stopped (because of a failure or for maintenance) before the pool is re-opened.
Backwashing must not take place when the pool is being used and should be done at the end of bathing for the day, normally in the evening. Allowing a period of at least 8 hours for the filters to settle and ripen will remove any remaining oocyst contamination of the pool water prior to the pool reopening. Air scouring before backwashing at a rate of about 32m/h is desirable to aid backwashing. Filter plant should have a flow meter or meters fitted between the circulation pumps and filters to monitor the system’s flow rate during normal operation, and backwashing rate. Backwash flow should be fast enough to fluidise the filter media bed, in accordance with manufacturers’ instructions – at least 30m/h.
Fluidisation of the bed should be checked visually through a viewing window. Backwashing protocol is critical; when neglected, it can for example be a factor in outbreaks of cryptosporidiosis. 5.6) Coagulation A coagulant should be dosed continuously and precisely, by chemical dosing pumps. Continuous low-level dosing of a coagulant is recommended for all pools (except those with membrane and ultrafiltration systems) to improve the filtration efficiency and increase the removal of any contaminants from the pool. This procedure significantly reduces the risk associated with any unseen faecal release. The recommended coagulant is polyaluminium chloride (PAC).
PAC should be dosed as far upstream of the filters as possible, but after the chemical controller’s sample point. PAC should be dosed continuously using a peristaltic pump. All grades of PAC should be dosed at a rate of 0.1ml/m3 of the total flow rate.
Coagulants should not be dosed by hand (unless specifically designed for this purpose) or via the strainer box. A wide range of disinfectants is available commercially. This CoP uses hypochlorite as a model for disinfection procedures. This is the commonest disinfectant, especially in public pools.
But the CoP does not intend to rule out the use of other effective disinfectant systems, including those that may be developed in the future. The first priority is to control entry to the pool hall using notices at reception saying that bathers:. With infections should not use the pool. With diarrhoea must not swim – then, or for 48 hours afterwards. Who have been diagnosed with cryptosporidiosis must not swim for 14 days after diarrhoea has stopped.
Pool water quality would be significantly improved if everyone using the pool showered with soap before entering the pool. Pre-swim showers should be provided, maintained in good working condition and bathers directed to use them before using the pool.
Toilets should be provided en-route to the pool, after changing and before showering, and everyone encouraged to use them before showering and swimming. Hand washbasins with liquid soap and hand-drying facilities should be provided.
Posters, signs and staff supervision should be used to enforce all operational procedures. These should cover the issue of when not to use the pool during and after diarrhoeal illness. 7.2) Babies and young children The water in ordinary public pools is not suited to very young babies: water temperatures and pool water chemicals may affect sensitive skin. For this reason, parents should be encouraged not to bring children under the age of 6 months to public swimming pools where they share the water with other general swimmers. Ideally, young children’s pools should be provided with separate water treatment and filtration and should be able to be emptied in the event of a faecal accident. Children still using nappies should use special swimming nappies or pants, which are designed to absorb and retain soiling.
Standard nappies are not adequate protection. Neither is suitable for children with diarrhoea; in this case they should not use the pool at all. Convenient nappy changing facilities should be provided in changing areas (these should be cleaned regularly), be equipped with basins for hand washing and have nappy disposal bins which are emptied regularly.
All floors in the pool hall area, changing rooms, toilet and shower areas should be thoroughly cleaned each day. 8.1) Cleaning the pool surround Pool surrounds should be cleaned at the start of each day by washing and scrubbing with 100mg/l chlorinated water (1ml of 10% w/w sodium hypo in 1 litre of tap water).
Proprietary chemical cleaners formulated for pool use may be necessary for stubborn dirt. Mechanical scrubber driers on separated extra-low voltage (SELV) pick up the water and solution used in cleaning and then dry the surface. These are ideal but should be emptied and disinfected and dried after each use. If a deck-level pool surround falls away (to drain) from the transfer channel, lowering the water level in the pool can keep any cleaning residue out of the pool water. 8.2) Cleaning the water line Deposits of dirt etc. Just above the water line of a freeboard pool can be cleaned off with a chemical-free scouring pad, using sodium bicarbonate or carbonate solution.
Operators should wear gloves and goggles. 8.3) Transfer channel Some pools have a transfer channel fitted with a drain valve, which is capable of being isolated from the pool water system. So for cleaning purposes the pool water level can be lowered (pool circulation stopped) so that water from the pool no longer flows down the channel. Then the transfer channel can be cleaned and it can also be used to take any cleaning residue from cleaning the pool surround.
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By opening the drain valve and thoroughly flushing, the cleaning residue goes to waste. 8.4) Cleaning agents Proprietary chemical cleaners should be avoided altogether if possible. They may contain surfactants that affect the monitoring of chlorine residual and cause foaming or phosphates, which promote algal growth. They may contain oxidising agents that give a false reading on water tests. Other compounds simply contain ammonia (they may smell of it) and could produce unhealthy pool conditions (through high combined chlorine levels).
If this is not possible every effort should be made to keep cleaning products out of the pool and any transfer channel. Ideally, there should be some way of draining all poolside washings to waste.
Certainly care should be taken to avoid outright incompatibility between cleaning and pool chemicals, which could be dangerous. Chlorinated isocyanurates – often called trichlor or dichlor – can react violently with neat hypochlorites (particularly calcium hypochlorite).
In general, reactions between acid and alkalis are potentially dangerous. 8.5) Proprietary cleaners where used If proprietary cleaners are required, they should be formulated for poolside use, and come from reputable suppliers (even though the target is to prevent them getting into the pool water). 8.6) Chemical cleaning agents and pool water Chemicals used for cleaning – whether for pool surrounds or the water line – should never be used when there are people in the pool. 8.7) Periodic removal of hard water scaling and body grease It may be necessary in all wet areas, pool surrounds, showers, changing rooms and toilets to tackle a build-up of lime scale from the water and/or body grease and oils from bathers. Use sodium bicarbonate or carbonate to remove any organic build-up such as body oils or grease. Use an acid-based cleaner (e.g.
Weak hydrochloric acid/or citric acid) for removing scale. Care should be taken when using acid descalers in the presence of cementitious grout as prolonged contact at too high a strength may dissolve the grout. It is important that no residue from these cleaning programmes returns to the pool water. 8.8) Showers Showers should be supplied with fresh water. Shower water should be stored at 60°C, and distributed so that it reaches at least 50°C at the feed to the shower and mixed at or within 2m of the point of use to 40°C (± 2°C).
Showers should run to waste. All showers installations should comply with HSG 274 part 2 The control of legionella bacteria in hot and cold water systems. All showers should be cleaned and descaled in accordance with HSG 274 part 2 requirements 8.9) Pool covers Pool covers should be checked regularly for any contamination, cleaned as necessary and disinfected with 100mg/l chlorinated water (1ml of 10% w/w sodium hypo/ 1 litre of tap water). 8.10) Pool equipment Any equipment, especially floating types, should be checked to ensure they are hygienic and clean before being used in the pool. This includes inflatable play devices, canoes, sub aqua equipment, arm bands, floats etc. They should be regularly cleaned physically, disinfected with 100mg/l chlorinated water solution (1ml of 10% w/w sodium hypo/ 1 litre of tap water) for 20 minutes, and dried prior to storage. 8.11) Transfer channels Deck-level transfer channels should be cleaned as required, at least once a month.
They should be drained and flushed out with 100mg/l chlorinated water (1ml of 10% w/w sodium hypo/ 1 litre of tap water) which can be returned to the balance tank. Grilles should be scrubbed weekly with 100mg/l chlorinated water.
8.12) Balance tanks Balance tanks should be inspected at least once a year and cleaned as necessary. Debris should be removed and inner surfaces brushed and flushed down with 100mg/l chlorinated water (see 8.1), which can be returned to the circulation system via the filters. 8.13) Pool bottom The pool bottom should be kept clear of contamination, algae, and general debris by daily sweeping, suction cleaning or other means. 8.14) Pool shell If a pool is emptied, then the bottom and sides should be scrubbed thoroughly with 100mg/l chlorinated water (1ml of 10% w/w sodium hypo/ 1 litre of tap water) before refilling. It should be flushed thoroughly to drain before refilling.
Check the integrity of the structure while the pool is empty. All operators should have, as part of the EAP, written procedures, which are practised and effective for dealing with the contamination involving faeces, blood and vomit. Faeces present the biggest risk, not least because of the threat from the chlorine-resistant protozoan Cryptosporidium (and its cousin Giardia). This section largely duplicates PWTAG Technical notes 2 and 17 on the PWTAG website. There is further information on the subject in note 30.
9.1) Assess the risk If faecal contamination has only been reported, and there is some doubt about the accuracy of the report, its presence should be confirmed by pool staff. If it cannot be confirmed, pool operators should assess the risk and may decide that the risk of harmful contamination is low and allow bathing to resume. This assumes that pH and disinfection are within normal limits. 9.2) Solid faeces Solid faeces are relatively easy to deal with.
It is unlikely that the perpetrator is suffering from an acute gastrointestinal illness and the microorganisms in it are relatively contained. The stools should immediately be removed from the pool using a scoop or fine mesh net and flushed down the toilet (not put in any pool drains).
There must be certainty that all the faeces have been captured and disposed of. There should be documented procedures for the use of the test kits and other test equipment, and operators should be given full training in their use for monitoring pool water quality. The documented procedures should detail actions for operators to take if there are unexpected test results, especially if they show the pool water chemical composition is either below or exceeding safe limits. 10.1) Pool water testing equipment The manual monitoring and measurement of the chemical condition of the pool water should be performed using appropriate test kits and following manufacturers' instructions.
Pool Plant Operations course Course Ref: STA/PPO. We run a 3 day level 3 qualification in pool plant operations. Cost £300 Aims This qualification aims to enable candidates to manage and maintain swimming pool, spa and interactive play feature operation via receiving the training necessary to reflect the most up-to-date requirements and standards for pool plant operation. Pre-requisites You must be 18 years of age or older to complete this training. Validity of award This qualification is valid for 5 years.
Length of course 33 notional learning hours:. 24 recommended guided learning hours. 9 non-contact guided learning hours Course information The pool plant operations qualification covers:. Industry led bodies and their recommendations and guidelines. Pollution and its removal, threat of disease such as legionnaires and how they are controlled. Principles of circulation and filtration and the requirements for regular maintenance.
How the physical characteristics of a swimming pool can be hazardous. Swimming pool ventilation and heating systems. The principles of water treatment. Microbiological testing. Analysis and interpretation of readings leading to corrective action.
Methods for recording results and maintaining records. Understanding the different types of residual and non-residual disinfectants and their use in water treatments. Understanding and awareness of current industry best practice, guidance and recommendations. Principles of health and safety and the relevant statutes. Develop an understanding of the environmental implications of operating and managing pools, spas and associated plant. Energy and cost efficiency. Assessment.
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V50d forklift manual. Complete a pre-course worksheet assignment. Complete the course manual.
National Pool Plant Operators Certificate Manual
Complete a 25 question multiple-choice paper with a pass mark of 18. Undertake practical water testing, analysis and interpretation. Complete a post course assessment sheet and return to course tutor. Revalidation This qualification requires revalidation every 5 years to update knowledge and demonstrate understanding. Candidates can revalidate either by undertaking the STA Pool Plant Revalidation/Conversion (including manual) Programme (available online at ) or by attending a one-day revalidation seminar. For further information please email.