1. Legionella
A type of bacteria that can cause a severe form of pneumonia known as Legionnaires' disease, typically contracted by inhaling aerosolized water droplets contaminated with the bacteria. Legionella thrives in warm water environments, particularly between 20°C and 45°C.

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2. Legionnaires' Disease
A severe type of pneumonia caused by the Legionella bacteria, characterized by symptoms such as fever, cough, shortness of breath, and muscle aches. It is often contracted by inhaling water vapor or mist contaminated with the bacteria.

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3. Legionella Risk Assessment
A thorough evaluation of a water system to identify risks for Legionella growth and exposure. This involves assessing water temperature, stagnation points, water flow, and areas where aerosols could form.

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4. Water Compliance
Refers to adherence to regulations and standards concerning water safety, quality, and treatment. In the context of Legionella, it involves ensuring that water systems do not harbor Legionella bacteria or create conditions conducive to its growth.

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5. Control Measures
Procedures and protocols put in place to reduce the risk of Legionella growth and spread in water systems. This includes temperature control, regular cleaning, disinfection, and the use of biocides.

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6. Cooling Tower
A structure used to dissipate heat from industrial processes, air conditioning systems, or power plants. Cooling towers are a common source of Legionella outbreaks if not properly maintained, as they create aerosols that can carry the bacteria.

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7. Hot and Cold Water Systems
Systems that provide hot and cold water to buildings, including domestic, commercial, and industrial plumbing systems. These systems must be regularly monitored to ensure that water temperatures are maintained within safe ranges to prevent Legionella growth.

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8. Water Temperature Control
Maintaining water temperatures outside the range favorable to Legionella growth. Water should be heated to at least 60°C in hot water systems and kept below 20°C in cold water systems. Temperatures between 20°C and 45°C encourage Legionella proliferation.

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9. Aerosolisation
The process of creating fine water droplets that can be inhaled into the lungs. Water systems that produce aerosols, such as showerheads, taps, and cooling towers, pose a greater risk for Legionella transmission.

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10. Stagnation
A condition where water sits still in pipes or tanks for an extended period, allowing Legionella bacteria to grow due to the lack of flow and temperature regulation. Stagnation is a common risk factor in systems that are infrequently used or improperly maintained.

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11. Biofilm
A slimy layer of bacteria and other microorganisms that form on surfaces in contact with water. Legionella can live within biofilms, making it harder to eradicate. Biofilms can develop in water tanks, pipes, cooling towers, and showerheads.

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12. Risk Management Plan
A documented strategy outlining how a building or facility will mitigate the risk of Legionella. This includes preventative maintenance, water temperature monitoring, disinfection practices, and response protocols in case of an outbreak.

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13. Water Sampling and Testing
Regular collection of water samples from various points in a water system to test for the presence of Legionella bacteria. Testing typically involves culturing water samples and analyzing them in a laboratory for bacterial concentration.

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14. Disinfection
The process of killing or removing harmful microorganisms, including Legionella, from a water system. Common disinfection methods include chlorine dosing, copper-silver ionization, and ultraviolet (UV) light treatment.

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15. Hot Water Storage Tanks
Tanks used to store hot water for domestic or industrial use. If not properly maintained, these tanks can be breeding grounds for Legionella, especially if water is stored at temperatures between 20°C and 45°C.

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16. Legionella Monitoring Program
An ongoing schedule for checking water systems to ensure that Legionella bacteria levels are within safe limits. Regular inspections, temperature monitoring, and microbial testing are essential components of a monitoring program.

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16. HSE (Health and Safety Executive)
The UK government agency responsible for regulating and enforcing health and safety laws, including those related to water safety and Legionella risk. The HSE provides guidelines and regulations for preventing Legionnaires' disease in workplaces and public buildings.

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19. ACoP L8 (Approved Code of Practice L8)
A UK document that provides guidance on the control of Legionella bacteria in water systems. It sets out the legal responsibilities of employers and those in control of premises to assess and manage Legionella risks.

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20. Legionella Control Program
A structured set of activities designed to prevent Legionella outbreaks, including regular system cleaning, temperature monitoring, disinfection, and risk assessments. The program should be tailored to the specific water systems in place.

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21. Legionella Treatment Protocol
A standardised set of actions taken when Legionella contamination is detected in a water system. This can include shock dosing with biocides, system flushing, cleaning, and further testing to confirm that Legionella has been eradicated.

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22. Water Temperature Monitoring
The continuous or periodic measurement of water temperatures in a system to ensure they remain outside the Legionella growth range (typically below 20°C for cold water and above 60°C for hot water).

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23. Flushing
The process of running water through a system, typically to remove stagnant water or contaminants, including Legionella. Flushing should be done regularly, especially in systems that are not used frequently.

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24. Risk Owner/ responsible person.
The individual or organization responsible for managing Legionella risks in a particular water system or facility. The risk owner is typically tasked with ensuring compliance with regulations, conducting risk assessments, and overseeing control measures.

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25. Isolation Valve
A valve used to isolate certain sections of a water system for maintenance or repairs. Ensuring proper use of isolation valves is important in managing Legionella risks, particularly in preventing contamination from reaching unaffected areas.

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26. Remedial Actions
Corrective measures taken in response to Legionella detection or failure to meet compliance standards. Remedial actions can include system disinfection, repairs, or modifications to water treatment protocols.

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27. Water Hygiene
A comprehensive approach to maintaining water systems free from harmful microorganisms, including Legionella. This includes routine maintenance, cleaning, monitoring, and the use of biocides or other treatment methods to ensure water safety.

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28. Compliance Audits
Regular inspections or assessments to ensure that a facility or organisation is meeting all regulatory requirements related to water hygiene and Legionella control. Audits often include a review of documentation, risk assessments, and monitoring procedures.

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29. Cooling System Maintenance
Routine inspection, cleaning, and disinfection of cooling systems (e.g., cooling towers, air conditioning units) to prevent the growth and spread of Legionella. This may include chemical treatments, flushing, and the replacement of components that encourage bacterial growth.

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30. System Design and Layout
The physical configuration of a water system, which can impact the risk of Legionella growth. Poor system design, such as dead legs or areas of poor circulation, can create conditions conducive to bacterial proliferation.

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This glossary provides essential definitions and explanations for key concepts within water compliance, particularly focused on managing Legionella risks. Regular monitoring, maintenance, and compliance with regulatory standards are crucial for ensuring the safety of water systems. Get in contact with Absolute Water Compliance for a free quote.