01 December 2015
A to Z of Swimming Pool Terminology
Baffled by the abundance of swimming pool terminology? Our jargon buster explains common terms and some include links to helpful articles on our website. We hope you find the A to Z helpful. If you spot a key term that is not included, email and let us know – we will consider adding it to the list.
Acid: One of two elements which determine the pH levels of your pool. Highly acidic water (low pH) can cause structural damage to both your pool and your pool equipment.
Algae: Especially during the hot summer months, algae can develop in your pool water. Algae are most commonly a collection of green micro-organisms that collect together in water – algae can heavily affect water clarity and make it unsuitable for swimming.
Algaecide: Algaecides are a chemical used to control and limit algae growth in pool water.
Alkali: After acid, alkali is the other main element, which determines the pH level of the pool. While very acidic water (low pH) can damage the pool, heavily alkaline water (high pH) can lead to calcium deposits and scale forming in the pool.
Bacteria: If pool water is not properly disinfected, swimmers can contaminate it with bacteria. This can lead to the spread of waterborne diseases and illnesses.
Backwash: Backwashing is an important part of regular pool maintenance. It involves reversing the flow of water back through the pool’s filter in order to remove the contaminants the filter catches.
Balanced water: The interaction and measurement of different pool chemistry factors, such as pH, temperature, hardness, and total alkalinity.
Bather load: The capacity of the pool in terms of how many people can use it at once.
Boilers: Boilers regulate the temperature of the pool water.
Basement pools: Indoor, subterranean pools built in a converted basement of a home.
Bespoke pools: Pools designed according to an individual’s preferences and tastes in every way: from the size, shape and style to finishes.
Booms: Submerged systems which allow a pool to be divided into different sections with an automated raised wall.
Bucket test: A simple method of checking if there is water loss in the pool and the possible cause. The test involves filling a bucket with pool water, partially immersing it in the pool, and, after pausing pump operations, comparing the water levels in the pool with that in the bucket to see how great the water loss is. A significant difference could point to a leak in the pool.
Chlorine: One of the most common pool disinfectants, and plays an important role in keeping the water sanitary and the pH levels balanced. Too much chlorine can irritate the skin, eyes and sinuses, while too little can lead to a risk of waterborne disease.
Cleaners (pool)C: Pool cleaners are a number of different chemicals, which, if used regularly as part of a maintenance programme, ensure the pool and its equipment, remain clean and sterile. Cleaning fluids include chlorines, algaecides, clarifiers and stain removers.
Coping: Usually a stone or tile material that defines the edge detail of the swimming pool or spa.
Closing the pool: Outdoor pools need to be closed during winter to protect the structure and equipment over the cold months. This process is also known as winterising the pool.
Control panel: Every pool has a customised control panel to operate aspects of the pool. This panel provides easy, convenient control over things like the water temperature, lighting, water features, automatic pool cover and the moving floor if one has been fitted to the pool.
Counter current units: A counter current unit allows bathers to use the pool for exercise by providing a strong current to swim against. Particularly suited to smaller pools.
Covers: Pool covers not only protect pools from debris, but they can also be used to help retain heat in the pool, cut down on energy costs, and reduce cleaning time and expenses. Different types of pool covers include solar, automatic, slatted, thermal, concealed, and winter covers.
Dehumidifiers: A heated pool creates a lot of moisture in the air in the room it is in. This can lead to mould and damp in your pool facilities. Dehumidifiers are vital in reducing air moisture and protecting your pool.
Design and build: Comprehensive design and construction of a swimming pool to an agreed specification, working with a pool specialist.
Electric heaters: Either in the form of electric resistance heaters or solar heaters, electric pool heaters heat the pool water. They are usually better suited to smaller home pools.
Electrical design: The design and blueprint for all the electrics that operate the pool, produced by the pool designer.
Experts: To ensure safety, pools are best designed and built by pool professionals who are qualified, expert in their craft and have proven experience. The same applies for servicing the pool; experts will maintain the pool and ensure it gives many years of use.
Filtration: Filtration systems keep the pool clear of dirt and debris. The most popular systems are sand and glass filters. Sand filters are less expensive and require a sand change every 3-5 years. Glass filters cost more, but the upside is that the glass media can last as long as 15 years before a change is needed.
Finishes (inside pool): The interior pool finish is made up of both the pool’s hard shell and the tiles or finish that the water interacts with directly. The type of interior finish installed has an impact on the colour and hue of the pool water.
Finishes (outside pool): The outside pool finish includes the tiling surrounding the pool and the walls and ceiling of the pool hall.
Fittings: Pool fittings include the drains and other plumbing parts used to pump water around your pool.
Flocculent: Flocculents are a chemical used to bind together smaller particles in order to make it easier for the filtration system to clear them from the pool.
Ground source heat pumps: Also known as geothermal heat pumps, these utilise the heat of the earth to warm pool water.
Heating: Heating is an important function of any pool system. The temperature of the pool heavily affects its water balance as well as the comfort and enjoyment of swimmers. There is a wide range of heating options for pools.
Hot tubs: Often built adjacent to a larger pool, hot tubs are small pools filled with hot, bubbling water. Hot tubs are used for relaxation or physical therapy.
Hydrotherapy: Hydrotherapy involves low-intensity exercise in a pool to relieve the symptoms of a range conditions, including arthritis.
Infinity Pool: Infinity pools are strategically built to appear as if they blend with a natural landscape – particularly lakes or oceans.
Inground pools: Inground pools are permanent pool structures built into the ground, usually in a back garden.
ISPE: The Institute of Swimming Pool Engineers is an organisation that represents individual pool engineers. It covers a breadth of services including promoting professional pool design, installation and maintenance of pools and pool equipment and engaging in the education and training of pool engineers. Learn more here.
Jets: Water jets feature in many pools, but particularly in hydrotherapy pools and spas. The powerful jets are used to relieve muscle tension and for relaxation.
Knowledge: Specific knowledge, qualifications and expertise are required to ensure the pool is technically well built. Working with a professional pool designer will open up many design possibilities – from a standard pool to complex installations such as infinity edge, linear deck slot, standard deck level overflow and letterbox surface flow systems. The design team should have CAD skills along with in-depth knowledge of advanced technology for pool design and build including efficient and environmentally friendly heating systems, water features, underwater lighting systems and moving floors.
Landscaping (around pools): To make outdoor pools really stand out, many pool owners decide to invest in some outstanding landscaping. The right landscaping can really make a pool something special.
Level deck pools: This refers to pools where the level of the water is exactly level with that of the pool surround.
Lighting: Pool lighting, be it in-water or out, is used to create depth and aesthetics in a pool.
Liners: Pool liners hold the water and form a smooth, safe surface. They prevent the interior of a pool from eroding from wear and tear.
Maintenance: Pool maintenance is vital to keeping a pool clean and pleasant to use for a long time. It includes cleaning and managing the chemical balance of the pool water, among other things.
Moving floors: Moving floors are built into swimming pools to enable the owners to adjust the depth of the pool water, for example, shallower for young swimmers. One of the biggest attractions of a moving floor is the ability to raise it level with the external floor and seal off the pool water completely. People can then stand on the solid floor and the area can be used for other functions such as parties.
Natural pools: These pools use no chemicals, with all filtration and sterilisation being done by organic filters and plants rooted in the pool system.
Opening the pool: This refers to the pool engineer re-opening an outdoor swimming pool, after it has been closed for the winter period (see closing pool for the winter above). The pool and plantroom are cleaned and the pool water chemistry is checked and adjusted as necessary.
Ozone sanitation system: An ozone sanitation system helps keep the pool water crystal clear and clean. It works by sanitising the water and increasing the overall effectiveness of the filtration system.
pH level: Refers to the chemical balance (or imbalance) of pool water. Learn more here.
Plantroom: The central hub of the pool’s operations, where the machinery used to run the pool is be located.
Pumps: These form the main feature of a pool’s water circulation and filtration process.
Purification systems: Used as an alternative to chemical treatments in order to sanitise the pool.
Pool Hall: A term used to describe the area where the pool is located, be it a public or private pool.
Pool Water Treatment Advisory Group: PWTAG provides guidance on swimming pools and spas in the UK. Read more here.
Quiet pumps: Quiet pump systems are designed to reduce the noise that is typically associated with pumps. Many modern pump systems incorporate sound dampening technology.
Refurbishment (or renovation): If a pool is getting old (or outdated!), tired looking, or underperforming, refurbishment is an excellent way to revitalise and modernise the pool. It also costs less than building from scratch.
Reliability: Check that the pool designer/builder and servicing company has a good record of accomplishment (eg are they SPATA members). Longevity, portfolio, testimonials and awards are good markers. Make sure that the pool company will complete the job as promised and on time.
Safety: Swimming pool safety measures are designed to protect bathers from a range of water-related hazards and accidents.
Sanitisation systems: Sanitisation systems include a wide range of pool technology, from pumps and filtration units to heaters and oxidisers. The goal of these systems is to keep the pool at a constant level of sanitisation.
Sauna: Used for relaxation, sauna rooms are generally made with timber (egAspen, Hemlock, Oak). Heat is provided by an electric heater that provides very high temperatures of dry heat. By adding water to the stones that sit on the stove the heat can be increased and also add humidity at the same time.
Servicing: To keep the pool running smoothly, the equipment should be serviced regularly by a pool service engineer. The engineer cleans the pump systems, filters and finishes, as well as manage the water chemistry.
Shock treatment: This involves dramatically raising the levels of chlorine in the pool for a short period in order to keep it sanitary.
Spa (also known as hot tub): A ‘tub’ of water used for relaxation or invigoration, usually including hydrotherapy jets. They can be installed stand-alone or as part of a pool installation, indoors or outdoors.
SPATA: Swimming Pool & Allied Trades Association, the governing body for the UK pool and spa industry.
Subterranean pools: Underground pools, built in a basement or underground space.
Stainless steel: Pools built with a stainless steel interior finish – provides a sleek, contemporary look.
Test kit: Pool test kits are used to test pH levels and water quality in the pool.
Tile finishes: Tiles have long been one of the most popular interior pool finishes. They come in range of materials including ceramic, porcelain, glass and stone and can be customised to create a unique design for each client.
Underwater lighting: Underwater pool lighting enhances the experience and appearance of a swimming pool, creating wonderful light shows when the sun goes down. Underwater lighting is also used in pools designed for therapeutic care (eg hospital aftercare). The coloured lighting is normally used as part of a sensory experience, which is often very soothing and used as part of various treatments.
Underground pools: Pools built in basements or underground spaces.
Ultraviolet sanitation systems: Sanitation systems which use UV light to disrupt or destroy bacteria and other micro-organisms which can form in the pool.
Vacuums: Pool vacuums are used to clear the water of dirt and debris - automatic and manual models are available.
Water evaporation: All pools lose a little water through evaporation caused by factors such as climate and humidity. If the water loss seems excessive, do the bucket test to see if there is a bigger issue (eg a leak).
Water features: Pool features that, while not necessary to the functioning of the pool, add a touch of glamour and personalisation.
Water level: This refers to how much water fills the volume of the pool shell.
Windows: Pools can be fitted with underwater windows made of clear acrylic transparent material which allows the bather to be seen whilst swimming under water.
Winterising the pool: Outdoor pools need to be closed during winter to protect the structure and equipment over the cold months. This process is also referred to as closing the pool for the winter.
Xtra special: Time for a treating in the sauna, spa, or home pool!
Young children (by the pool): Always keep a watchful eye on young children in and around the pool area. Young children should be supervised at all times and safety precautions and procedures followed to the letter.
ZZZ: Snooze by the pool - time to take a break and relax with a long, cool drink!
If you have any questions about caring for your pool or spa call Chris Walker, Head of Servicing at London Swimming Pool Company - 020 8605 1255.