Management and Control of Legionella Procedure

Transcription

1 Management and Control of Legionella Procedure Version Number 3.0 Effective from 24 April 2017 Author: Head of Operations Estates and Facilities

2 Document Control Information Revision History incl. Authorisation: (most recent first) Author Summary of changes Version Authorised & Date Darren Kibble Update to incorporate Media City UK, New Adelphi and David Lewis Changing Rooms V3.0 Director of Estates and Facilities: 24/04/17 Darren Kibble Updated to reflect staff structures and moved onto new template V2.0 Director of Estates and Facilities: 01/10/15 Mike O Connor Document Developed V1.0 Health and Safety Committee: 2008 Policy Management and Responsibilities: Owner: These procedures are issued by the Director of Estates and Facilities, who has the authority to issue and communicate procedures on Legionella and has delegated day to day management and communication of the procedures to the Head of Operations. Others with responsibilities (please specify): All subjects of the procedures will be responsible for engaging with and adhering to these procedures. Author to complete formal assessment with the following advisory teams: Equality Analysis (E&D, HR) Equality Assessment form 1. This is mandatory. Specify date completed and brief outcome. the completed EA to Equality@salford.ac.uk Legal implications (LPG) 2. N/A Information Governance (LPG) 3. N/A Student facing procedures (QEO) 4. N/A UKVI Compliance (Student Admin) 5. N/A Consultation: Staff Trades Unions via HR Students via USSU Relevant external bodies (specify) 1. N/A Review: Review due: Document location: 2 years by April 2019 (Note: LPG send a reminder to review is due) University Policy & Procedure Pages University of Salford Policy pages The owner and author are responsible for publicising this policy document. Page 2 of 24

3 1.0 Scope and Objectives The objective of this procedure is to enable the University to meet its legal responsibilities to prevent the proliferation of Legionella in water systems within University properties. The procedure details the need to carry out risk assessments, maintain safe systems of work and the steps to take in the event of a Legionnaires disease outbreak. Specifically, the precautions adopted will ensure the risks from legionella bacteria proliferation are avoided by: Avoiding water temperatures between 20 o C and 45 o C and conditions that favour the growth of legionella bacteria and other micro-organisms; Avoiding water stagnation, which may encourage the growth of biofilm; Avoiding the used of materials that harbour bacteria and other micro-organisms, or provide nutrients for microbial growth; Controlling the release of water spray; Maintaining the cleanliness of the system and water in it; Using water treatment techniques; Taking action to ensure the correct and safe operation and maintenance of the water system. 2.0 Definitions A glossary of terms is included at Appendix Procedure Roles and Responsibilities The majority of the Salford University properties contain some kind of water storage system, plant and equipment which is susceptible to bacterial colonisation. Therefore, measures need to be taken and procedures put in place to prevent the legionella bacteria from proliferating within the building water systems owned, managed or maintained by the University of Salford. The principles behind the University s management and control of legionella risk procedures are: Where practicable, eliminate or reduce the water storage. To take all reasonable and practical precautions to manage and control legionella bacteria in water systems. To protect the people occupying and visiting their premises, as well as passers-by, within the vicinity of the institution from this risk. To ensure that appropriately trained and technically competent and experienced staff are available and resourced to adequately manage water systems and associated legionella control. Page 3 of 24

4 To prevent legionella exposure by ensuring that appropriate risk assessments and safe working practices are identified and followed by all relevant university staff, Contractors and Sub-Contractors. To ensure the procedures for the control of Legionella bacteria in water systems, plant and equipment within the University of Salford properties shall be in accordance the Approved Code of Practice HSC document L Risk Assessment To manage and control legionella bacteria in water systems the University of Salford will carry out risk assessments for all potential areas of legionella risk for their properties in accordance with the Management of Health and Safety at Work Regulations 1999 and the Control of Substances Hazardous to Health Regulations 2002 and in line with the requirements of HSG274 Part 2: Appendix 2.1; Legionella risk assessment. The risk assessment will identify the hazards, decide who might be harmed and how, evaluate the risks and decide on precautions, record findings and implement them and review the risk assessments and update them as necessary. The greatest areas of risk of the proliferation of legionellosis on the University estate is in hot and cold water systems, thermostatic mixing valves, calorifiers, storage cylinders, water systems with evaporative condensers, little used outlets (dead legs), water storage tanks, air conditioning systems, humidifiers, spa-baths/pools, pools, shower heads, emergency showers, eye wash sprays and lathe and machine tool coolant, a water fountain and any system which provides aerosols that may exceed a temperature of 20ºC. This list is not exhaustive. A full building stock and individual building risk assessment to identify sources of legionella risk and appropriate reporting of those potential sources shall be carried out leading to an asset inventory and maintenance management system to control and reduce the risk of legionellosis. This risk assessment will be carried out by an appointed competent person and updated as and when found necessary but at a minimum of two yearly intervals or following significant changes to the hot and cold water services. A list of buildings owned by the University of Salford that shall be updated at the time of acquisition or disposal and filed in the Buildings List in the Appendix of this document. An inventory of building assets associated with legionellosis risk will also be filed in the in building specific risk assessment reports. An Action Plan arranged from the findings of the risk assessment surveys will be produced and prioritised to reduce legionellosis risk and this will be reviewed every two years as a minimum or when significant changes take place to the buildings water or other legionellosis risk assets. 3.2 Action Plan The prioritised risk assessed action plan will be utilised to control and manage legionella risk in the University water systems and other potential sources. Certain risks may need to be formed in to project work packages and bids made against the Universities Legislative Major Maintenance Budget. Other risk reduction measures may involve minor system changes or planned preventative maintenance regimes to be implemented and controls carried out. All work shall be prioritised and be based on the risk level to the persons likely to be affected Page 4 of 24

5 particularly groups of persons associated with a high risk of acquiring a legionellosis. Risk reduction measures to either eliminate or to reduce the risk level to low and safely managed should be adopted. On new, refurbishment or major water system change projects an individual action plan will be put in place and all risks assessed and dealt with in accordance with these procedures. Building files should contain all sources of legionellosis risk and how they can be maintained complete with all necessary certifications issued to the operations section. 3.3 Controls and Implementation of Safe Systems Suitable and sufficient control systems will be maintained within the University to reduce and manage the risk of legionellosis. A Controls Matrix will be held and updated to control and manage potential sources of legionellosis within University buildings this will identify the following fields of information: Task to be undertaken Frequency of treatment Responsibility of task or process The management task or process Standards to be met Ratification Action A copy of this Controls Matrix will be an appendix to this document and managed through the Up2Date software package This cloud based software enables buildings and their assets to be managed in relation to Legionella at given time frequencies i.e. via PPMs (Planned Preventative Maintenance). The system is robust and has an audit system in place. Any associated legionella remedial work is raised in CAFM (Facilities Management System) and the work order number then recorded in the Up2Date System. On the pass over of Building Files from new or refurbishment projects these will be scrutinised and the Controls Matrix assessed. Any new controls will be added to the matrix. All new controls required will then be uploaded in to the Up2Date system be it a routine or statutory PPM requirement. Control checks will be adopted consistent with HSE document HSG274 Part 2 and are contained in the Controls Matrix. These will be fully identified by risk assessment as identified in section 2.0 of this document. Additional information on specific job task procedures is attached to the appendix of this document. Hot water systems are controlled by thermal disinfection, maintaining the temperatures as detailed in HSG274 Part 2 and temperature monitoring as per the procedure in the appendix. Cold water systems are subject to a similar temperature monitoring regime. Chlorination or thermal disinfection treatments will be subject to a risk assessment before the commencement of any works. The risk assessment will address all potential risks including risks to the operatives carrying out the work, any persons likely to be affected and the risks from chlorination chemicals or other substances used. The water system shall not be put in use until a compliance certificate has been issued to Estates and a responsible person has deemed the system safe to be used. Page 5 of 24

6 To ensure adequate communication and co-ordination takes place within Estates regular quarterly meetings will be held to discuss water system and legionella management. Minutes from those meetings will be produced with actions points as necessary and then circulated within Estates and HS&W. Should any system controls break down then an immediate report should be made to the responsible person followed up immediately as soon as practicably possible in writing. Any person(s) who know of any breaches or breakdown of system controls or any other unacceptable water or legionellosis risks have a duty to immediately report these to line management or the Estates Safety Advisor. 3.5 Record Keeping Record keeping is an essential part of the legionella management procedures and all persons are responsible for keeping their part of the system records up to date. Estates keep a log book in each building for water systems and legionella information and local documents relating to water systems are filed in that source. Full records are also maintained in the Up2 Date system. Examples of information sources to be filed include test certificates, copies of risk assessments, monitoring and audit reports and other related documentation. Information relating to water temperature management and building water system line diagrams are held on the University Estates shared network drives. I:\Maintenance Procedures\Contract Maintenance\Water Systems Management V:\Services\E&PS\Function Building Files\ Up2Date records electronically all PPM jobs completed with operative s names and dates of job action. 3.6 Training Suitable and sufficient training at the correct risk based level will be attended by employees who manage, design and work on systems that may give a legionellosis risk. This training will form part of the Estates staff training programme and advice on the suitability of courses will be discussed and agreed with HSW. 3.7 Failure of Water Sample or Suspected Legionella Outbreak Microbiological monitoring should be carried out where there is doubt about the effectiveness of the control regime or it is known that recommended temperatures, or other precautions, are not being consistently achieved throughout the system. If a water sample microbial levels breach the guidance levels given in HSG274 Part 2: Table 2.2 for legionella bacteria, the results will be analysed and discussed with the laboratory concerned and the Associate Director of Health, Safety and Wellbeing or an appointed safety advisor. Advice may be taken from the University s appointed Legionella Consultant, if appropriate. The Duty Holder will be kept informed of progress at all times. The outcome may be that additional samples need to be taken or in other or extreme cases the authorities informed. Page 6 of 24

7 If a Legionella outbreak case is suspected, this will activate the major incident management plan. The Associate Director of Health, Safety and Wellbeing will work in closely with the Duty Holder and his staff to minimise future risk situations based on agreed solutions with external authorities or advisors if necessary. The University will follow the guidance as laid down in HSE Document HSG274 Part 2: Appendix 2.3 Action to take if there is an outbreak of legionellosis. Copies of this document will be available for reference the in Estates Division. 4.0 Related Documentation Legionella Policy. 5.0 Monitoring and Performance of Procedure Monitoring of legionella management will be carried out as a line management function and this will be further supported by Up2Date software. An annual water systems and legionella management audit will be carried out by an external auditor appointed by the Duty Holder. The audit will consist of meeting Estates staff, carrying out on-site inspections selected by the auditor, assessment of record keeping and the issue of an audit report as a minimum requirement. On receipt of the audit report all points raised will be reviewed alongside internal observations or comments and system reviews will be undertaken as appropriate. The audit report will be discussed at the next water system/ legionellosis meeting held in Estates. The audit report will be made available to the Duty Holder, the Responsible person and the Director of HSW as a minimum. 6.0 Training and Support Where relevant, specify training and support for the procedure. 7.0 Appendices List any appendices including flowcharts, tables or procedure maps. Appendix 1 - Inventory List of University Buildings Appendix 2 - Controls Matrix Appendix 3 - Managing the Risk of Proliferation of Legionella in Water to Water Calorifiers Appendix 4 - Working on and Draining Down a Calorifier Appendix 5 - List of Relevant Planned Preventative Maintenance Job Tickets (PPM s) Appendix 6 - Project Design Guide: Hot and Cold Water Systems Appendix 7 - Glossary of Terms Page 7 of 24

8 Appendix 1 - Inventory List of University Buildings Adelphi Building Adelphi House Allerton Annexe Allerton Building Alumni House Brian Blatchford Building Centenary Building Chapman Building Clifford Whitworth Cockcroft Building Crescent House David Lewis Changing Rooms Faith Centre Faraday Building Gilbert Rooms Humphrey Booth House Jack Goldberg Building Joule House Lady Hale Building Mary Seacole Maxwell Building Maxwell Hall Media City UK New Adelphi Building Newton Building Peel Building Technology House Sports Centre University House The Old Fire Station Former NatWest Bank and Fire Station Mews Page 8 of 24

9 Appendix 2 - Controls Matrix Task Frequency Responsibility Management Process Standard to Meet Ratification Action Sentinel taps (CW) Temperature checks Sentinel taps HW Temperature checks TMV (HW) Temperature checks Monthly Allocated operative CAFM PPM Water temp. should be below 20 C after running the water for up to two minutes Monthly Allocated operative CAFM PPM Water temp. should be at least 50 C within a minute of running the water Monthly Allocated operative CAFM PPM The water supply to the TMV temperature should be at least 50 C within a minute of running the water Leader to investigate and take remedial actions as necessary to manage risk level Leader to investigate and take remedial actions as necessary to manage risk level Leader to urgently investigate and take remedial actions as necessary to manage risk (possible scald risk) TMV (HW) Temperature checks Weekly Energy Manager Use a temperature probe via BMS record on shared drive bring to Leader attention urgently any risk temperatures The water supply to the TMV temperature should be at least 50 C within a minute of running the water Leader to urgently investigate and take remedial actions as necessary to manage risk level (possible scald risk)

10 Water leaving and returning to a calorifier (HW) Weekly Energy Manager to do BMS and Leader to read results as system University network shared drive and CAFM job ticket reminder to examine results Outgoing water should be at least 60 C return at least 50 C Leader to investigate and take remedial actions as necessary to manage risk level Visual check on internal surfaces of calorifier for scale and sludge. Annually + Sixmonthly Leader to organise programme and executed by operatives CAFM PPM Leader to inspect tank condition. Incoming cold water inlet (at least once in the winter and once in the summer) Check tank CW temperature remote from ball valve and mains temp. at ball valve. Visually inspect cold water storage tanks and carry out remedial work where necessary. Six- monthly Allocated operative CAFM PPM The water should preferably be below 20 C at all times if above this temp. provider to be informed or risk managed. Ball valve outlet temp. ideal. Six- monthly Allocated operative CAFM PPM The water should preferably be below 20 C at all times if above this temp. provider to be informed or risk managed. Annually Allocated operative CAFM PPM Staff should be trained by Mechanical Team Leader on tank standards to be achieved to meet Leader to investigate and take remedial actions as necessary to manage risk level Leader to investigate and take remedial actions as necessary to manage risk level. Consider fixing remote temp monitoring on BMS. To clean, re-coat or renew tank as required and ensure compliance to Water Regulations and L8 Page 10 of 24

11 satisfactory tank standards Standards Representative number of CW taps on a rotational basis Annually Leader & CAFM Officer to plan and agree PPM detail CAFM PPM Water temp. should be below 20 C after running the water for two minutes Leader to investigate and take remedial actions as necessary to manage risk level Representative number of HW taps on a rotational basis Annually Leader & CAFM Officer to plan and agree PPM detail CAFM PPM The water temperature should be at least 50 within a minute of running the water to ensure whole system is reaching the required temp. Leader to investigate and take remedial actions as necessary to manage risk level Arrange for samples to be taken from HW calorifiers and note condition Annually Leader to arrange with lab and record CAFM PPM Condition of drain water to meet satisfactory standard as agreed with consultant. Act on water sample information. Shower Heads Quarterly or as necessary by risk assessment Allocated operative CAFM PPM Dismantle, clean and descale shower heads and hoses. Report and concerns to line management for remedial action to be considered. Little used outlets Weekly Allocated operative CAFM PPM Flush through and purge to drain, or purge to drain immediately before use, without release of aerosols. To reduce number if at all possible. Carry out risk assessment if inspections identifies concerns. Page 11 of 24

12 Emergency showers or eye wash sprays Six- monthly or more frequently if recommended by manufacturer Allocated operative CAFM PPM Flush through and purge to drain avoid aerosols. If water sample not clear investigate further. Lathe and machine tool coolant systems Six-monthly Allocated operative CAFM PPM Clean and disinfect storage and distribution system. Ensure coolant system satisfactory for use if not ensure replacement PPM in place. Shunt Pumps Monthly Allocated operative CAFM PPM To ensure temperature is constant on both sides of pump If temperature ii not consistent investigate pump operation immediately Pool / Spa Pool Maintenance Currently managed via the leisure centre using an external contract company for maintenance and testing. Page 12 of 24

13 Appendix 3 - Managing the Risk of Proliferation of Legionella in Water to Water Calorifiers Salford University Estates & Facilities need to manage a risk of the proliferation of legionella in a number of hot water calorifiers within its building. In the main hot water for kitchen, wash basins and showers on and off campus is generated by way of direct gas fired water heaters. These hot water heaters have gas burners directly under the base of the storage vessel, when the burner is running the water within the vessel is fully heated up, usually way in excess of temperature at which legionella would reproduce. The ACoP L8 Page 38 Para a requires The storage capacity and recovery rate of the calorifier should be selected to meet the normal daily fluctuations in hot water use without any drop in the supply temperature i.e. the stored water should not drop below 60C This positive and complete heating up is due to the high temperature difference between the gas burner plate and the water in the vessel. However, the university has a number of older type water to water calorifiers heated via internal water coils, in these systems there is no guarantee that all the water in the storage vessel will be heated up above the temperature band of proliferation. It is also known that the heater tubes in a water to water calorifier usually enter the vessel some way up the side of the vessel and therefore the water below the tubes may be at some temperature much lower than the middle or upper part of the vessel, this is known as stratification. The University Of Salford Estates & Property Service therefore accepted that there is a risk which needs to be addressed, the method of reducing this risk and providing a process and the maintaining and monitoring of that process is set out below. The method accepted is to be temperature pasteurisation, heat treatment to destroy micro-organisms. Risk Assessment We have carried out a specific risk assessment for this process as required under the Management of Health and Safety Regulations 1999 The Water to Water Calorifiers in the group are: The Pool Plant Room (Leisure Centre) (two calorifiers) The Process Under normal conditions the water in all of these units would be brought up to temperature during the day and left to cool down at night. All of the units are controlled via the BMS system and their temperatures are controlled also via the BMS.

14 Regardless of any other process, every Wednesday evening at midnight the five calorifiers are heated up extraordinarily, the secondary pumps are held turned off and water is therefore held in the vessel and not allowed to circulate through the secondary systems. Heat is continually applied to the calorifiers until such time as the internal water temperature is raised to 70ºC, it is then held there for one hour and after allowed to cool down, such that no scalding can occur in the early morning to cleaning staff etc. Monitoring The whole process is automatically monitored graphically via the BMS. A PPM is in place for Operational Staff to monitor the process. Periodic Water Sampling from Water To Water Calorifiers Under direct instructions from the University s Water and Legionella Consultant (Mr. David Harper) it has been deemed un-necessary to take water samples from these calorifiers and also considered that pasteurisation will be a robust enough process to destroy any legionella bacteria. Page 14 of 24

15 Appendix 4 - Working on and Draining Down a Calorifier Operation Description Working on and draining down domestic calorifiers could involve such tasks as inspection, cleaning and modification of calorifiers and all associated pipe work and pumps etc., in connection with the vessel. This work should only be carried out by competent and trained persons who are given adequate training and instructions by competent supervision. Risk Assessment Exposure to the Legionella bacteria can cause serious illness or in the extreme case a fatality. It is important that these procedures are followed in the full as exposure to such risks are associated with calorifiers maintenance. The risks are to the operative carrying out the work, and person entering the work area and the users of the building if exposed. The greatest hazard is from legionellosis from legionella bacteria and illnesses from other bacteria present. Legionellosis (including Legionnaires disease) is normally contracted by inhaling the Legionella bacteria deep into the lungs through tiny droplets of water (aerosols) i.e. by the work-persons breathing in water vapour that is contaminated with the bacteria. Other risks to be managed include other inhalation risks, eye contact, skin contact, ingestion, lifting and handling. Hazards such as heat sources, plant and equipment, electricity etc., all need to be assesses. The risk assessment should include the provision of Personal Protective equipment as necessary. Should a Calorifier a require a Chlorination process at the time of working or cleaning down then this should be part of or a subject to a risk assessment. Calorifiers can be heavy in construction and also their associated parts. If a complicated lifting and handling procedure is required then a site specific lifting and handling risk assessment should be carried out before work commences. A suitable and sufficient risk assessment will be carried out for all work associated with the maintenance of calorifiers. Although a generic risk assessment may be carried out the local work conditions must be taken in to account. The best course of risk reduction is to remove calorifiers whenever practicable to do so to eliminate or reduce such risks. The Process Working on and draining down domestic calorifiers could involve such tasks as inspection, cleaning and modification of calorifiers and all associated pipe work and pumps etc., in connection with the vessel. This may involve taking a calorifier off/ on line (draining down and cleaning a calorifier) and chlorinating of the system. A method statement for taking a Domestic Hot Water Calorifier Off/On Line is required to manage all significant risks will be provided by the supervisor. All operatives required to fully comply with this process requirement. If in doubt, ask your Supervisor, do not put yourself at risk. Page 15 of 24

16 For low level risk work such as inspection and temperature monitoring then general plant room safety rules will apply and those persons carrying out such work should be experienced of such job tasks and also the working environment. When draining down a calorifier the drain down valve should have a temporary pipe securely fixed and this then drained into a bucket or wet drain source to prevent aerosols. The temperature of water storage should be at a safe level to prevent burns and scalds before the drain down process begins. Eye protection must be worn when working on or cleaning out Calorifiers or their constituent parts i.e. the pump etc. Eye protection must be worn in the form of safety goggles to prevent dirt, sludge, rust metals and the like entering the eyes. Skin contact should be avoided from all sludge, dirt, sharp metals and the like. The minimum clothing to be worn would include gloves, bump cap and wet suit. Ingestion of sludge and dirt from the Calorifier should be avoided. The use of a facemask will prevent such ingestion taking place. All lifting and handling is to be carried out in a safe manner and in accordance with the University lifting and handling procedures. All persons who are not directly involved with the calorifier works should be excluded from the work area and especially from the risk of aerosols. All work areas such as plant-rooms should be kept clean and tidy to ensure the work is carried out in a safe manner and to avoid slips, trips and falls. Any materials or items of plant removed for calorifier maintenance should be stored in a safe manner to prevent accidents. Do not block walkways if possible. Provide barriers and signage as necessary. Should the Calorifier be subject to Chlorination at the time of working or cleaning procedures for chlorination of water systems will apply. The work required on calorifiers must be communicated to the Operations Engineer or Building and Mechanical Manager before any work starts on site. Calorifiers being worked on should be sign posted to say Warning Work in Progress. So the work activity is communicated to all. Page 16 of 24

17 Appendix 5 PPM Specification Sheet Hot &Cold Water Outlet Temperature Checks Hot Water Outlet Temperature Checks Monthly Shower Head and Spray Tap Checks Water System Treatment CAFM PPM Ref. Number PPM Ref. No B006 PPM Ref. No B007 PPM Ref. No B008 PPM Ref. No B002 6 Monthly Cold Water Tank Inspection PPM Ref. No B014 Audit Existing Legionella Risk Assessment Records Thermometer Calibration Procedure Emergency Shower Water Checks Emergency Shower Water Temperature Check Procedure (To be read in conjunction with Spec. B032) Monthly Check De-Stratification Pumps Annual Inspection Thermostatic Mixing Valves Flushing of Underused Outlets for Showers, Tap Outlets, etc. - to include cleaning and disinfection Taking Water Temperatures to Incoming Mains and Sentinel Taps (to be developed) Fountain Maintenance PPM Ref. No B026 PPM Ref. No B030 PPM Ref. No B032 PPM Ref. No M058 PPM Ref. No M063 As required PPM Ref. No M130 Page 17 of 24

18 Appendix 6 - Project Design Guide: Hot and Cold Water Systems 1. Purpose The aim of the Design Guide is to advise on the measures necessary to control Legionella bacteria in the Universities hot and cold water systems by adopting HSE Documents ACOP L8 & technical guidance HSG274. To be implemented on all Projects involving the installation of new and the alteration of existing water supplies To provide Project Managers and Consultants with knowledge of Legal and Technical requirements for the installation and alteration of hot and cold water systems and the installation of air conditioning systems within the University. 2. Legal Aspects There are numerous statutory regulations governing the requirements of hot and cold water systems as listed below: Statutory Regulations Management of Health and Safety at Work Regulations Control of Substances Hazardous to Health Regulations(COSHH) Chemical (Hazard Information and Packaging for Supply)Regulations(CHIP) Building Regulations Water Industry Act Water Supply(Water Fittings)Regulations Water Supply (Water Quality)Regulations Notification of Cooling Towers and Evaporative Condenser Regulation Construction(Design and Management )Regulations(CDM) Reporting of Injuries, Diseases and Dangerous Occurrences Regulations(RIDDOR) Health and Safety (Consultation with Employees)Regulations Personal Protective Clothing Regulations(PPE) Provision and use of Work Equipment, Regulations All come under the common umbrella of: The Health And Safety at Work Act 1974 Relevant sections to the Approved Codes of Practice Section 2 Section 3 Section 4 Section 6 General Duties of employers to their employees General Duties of employers and self-employed to others than their employees General Duties of person in control of premises to users Duty of manufacturers, designers, suppliers and installers, to ensure goods and services are safe Page 18 of 24

19 Section 7 Section 8 Section 17 Section 33 Section 40 Duty of employers to themselves and others Duty not to interfere with or misuse things provided pursuant to certain provisions Use of approved code of practice in criminal proceedings Offences Onus of proving limits of what is practicable 3. Medical Legionellosis is the term used for infections caused by Legionella pneumophila and other bacteria from the family Legionellaceae. Legionnaires disease is a pneumonia that principally affects those who are susceptible due to age, illness, immuno-suppression, smoking etc. and may be fatal. Legionellae can also cause less serious illnesses such as Pontiac and Lochgoilhead fevers which can affect all people. Infection is attributed to inhaling legionella bacteria, in water droplets which are small enough (<5 μm) to penetrate deeply into the lung. Legionella bacteria are widespread in natural sources of water. They may enter man-made systems where, under favourable conditions, they can multiply. If water droplets are created and dispersed into the atmosphere from those systems then people in the vicinity may be at risk. Most cases and outbreaks of legionellosis have been attributed to water services in buildings, cooling towers and whirlpool spas. Other sources have been identified in foreign outbreaks including a humidification system, industrial coolants and respiratory therapy equipment. 4. Controlling the Risk A number of factors are required to create a risk of legionellosis: The presence of legionella bacteria Conditions suitable for the proliferation of those bacteria A means of creating and disseminating an aerosol The presence of individuals who may be exposed. The conditions favouring the proliferation of legionella are: Moisture Temperature between 20 C and 50 C Availability of nutrients, for example from sediment, sludge, organic material, scale, rust, compatible organisms and materials used in construction of water systems Presence of biofilm (bacterial slime) on surfaces in contact with water. Page 19 of 24

20 The elimination of as many of these conditions as possible forms the basis for control of the risk. Treatment regimes to eradicate or reduce the proliferation of legionella (based on physical or chemical disinfection of water systems) also help to control the risk but do not prevent it. The principal control measures for preventing the prolification of legionella bacteria include:- Controlling the release of water spray Avoidance of water temperatures and conditions that favour legionella bacteria and other micro-organisms Avoidance of water stagnation Use of materials approved by the Water Regulations Advisory Scheme(WRAS) operated on behalf of all the statutory water undertakings of the United Kingdom by the Water Research Centre Maintenance of the cleanliness of the system and water in it Where necessary, the use of water treatment techniques. 5. Development Design Standards At the start of each project a physical inspection of any water system that may be affected by the project or where it affects the project from incoming supply point to final outlet will be undertaken. This inspection will include: Tracing all pipework systems and checking condition of pipe and any insulation. Measuring the time taken to achieve recommended temperatures at hot and cold water outlets. Checking layout and arrangement of all storage tanks, calorifiers and circulation pumps. Measure system temperatures of calorifiers and at strategic points along distribution pipework to ensure compliance. Identify redundant or little used outlets and pipework deadlegs, which could be removed. Upon completion of this inspection, the responsible person will arrange for any remedial works to minimise risk. Whole building assessments will need to be reviewed in the following circumstances: Changes to the water system or it s use(changing from tank feed to mains feed) Changes to the use of the building in which the water system is installed (possible need to downsize storage tanks and pipework) Eliminating the risk must be the first consideration in any design or alteration proposal. Reducing the risk and controlling the risk will be the secondary consideration and must include best practice. Page 20 of 24

21 The Consultant and Project Officer will make arrangements to implement the following Design Considerations: Direct cold mains water systems must be considered in all new designs in preference to providing cold stored water however if required for back flow prevention or if design assessment requires cold water storage, it must be designed and sized to hold the minimum amount of water possible. Ensure cold water storage tanks are constructed to meet current water bylaws, discourage stagnation using good practice when siting supply and outlet connections, have a minimum turnover of at least once per 24 hour period and maintain stored temperature below 20C. All tanks must comply with the Water Supply (Water Fittings) Regulation 1999 and must be easily and readily accessible for both maintenance and monitoring. All cold water pipework must be appropriately insulated and isolated from heat sources. Preference shall be given to using instantaneous preferably direct fired gas water heaters with hot water stored at a minimum 60 deg C. For new installations a minimum distribution temperature of 55 deg C should be available at any outlet within 30 seconds of opening the tap for all other existing installations upgrades and refurbishments a temperature of 50 deg C must be achieved within 1 minute of opening the tap. On recirculation systems the return temperature to the calorifier must be greater than 50 deg C. Where the water temperature is reduced at point of use by use of thermostatic mixing valves the leg from the distribution circuit must not exceed 3mts and the leg from the blender must not exceed 2mts. As a minimum standard, any equipment fitted to the water system infrastructure must be attached via approved double check valves to remove the risk of any back siphoning into the University s water system. Ensure all taps and associated pipework systems that are not used or infrequently used are removed. Ensure that water temperature from outlets used by children, disabled or elderly persons are blended down to no more than 43C to prevent scalding. Where this is deemed unnecessary for other users, permanent labels shall warn of scald hazard to users. Modify circulation systems to remove all dead legs and blind ends. No flexible braided hoses, even those with WRAC(Water Regulations Advisory Scheme) stamps shall be used on any University water system. That only materials that comply with The Water Supply (Water Fittings) Regulations 1999, will be used i.e. those that do not promote bacterial growth. All new and refurbished hot and cold systems and any systems that have been out of use without regular flushing on a weekly basis must be cleaned and disinfected in accordance with BS 6700:1987,section 3 clause 13.9 or as amended before being re-instated for use. Spray taps must not be used with a TMV (Thermostatic Mixing Valve). The above list is a guide to good practice and is not intended to be exhaustive or complete. Page 21 of 24

22 6. Consultant Qualification and Training Any consultant designing and specifying alterations to the University s water systems shall work in accordance with the University s Water Management Policy, including complying with any written or verbal instruction from an officer of the University. Only suitably trained, qualified and resourced staff will carry out design and manage work on the University s water systems. All work will be undertaken in such a way as not to compromise the safety of the water system. Only approved materials and components will be used. All consultants must demonstrate that their staff are competent and suitably qualified to work on water systems prior to commencement of any works. Contractors carrying out design or any consultant working on behalf of the University shall be responsible for the effective design and management of all capital schemes including comprehensive commissioning of new systems. Fully detailed as fitted drawings, that satisfy the requirements of the Water Regulations, will be provided upon completion of the works. Where disinfection is necessary, works shall be undertaken out of normal occupancy hours to ensure that water system users do not come into any contact with chemical agents used to clean and dose the system. Staff employed on water systems shall receive regular training and instruction to ensure operatives understand safe working practice. 7. Records It is the contractors and consultants duty to provide the University with recorded information through the project officer to maintain its statutory records, this should include: Completed work, manufacturer and material used, commissioning tests, certificates of disinfection, and as fitted drawings. In the case of new build all relevant information will be included in the Health and Safety file on handover: Design risk assessments, completed work, manufacturer and material used, commissioning tests, certificates of disinfection and as fitted drawings. Page 22 of 24

23 Appendix 7 Glossary of Terms Aerosol - A suspension in a gaseous medium of solid particles, liquid particles or solid and liquid particles having negligible falling velocity e.g. fine mist of water produced by a shower spray head, small enough to be inhaled. Bacteria - (singular bacterium) a microscopic, unicellular organism. Biocide - A substance which kills micro-organisms. Biofilm - A community of bacteria and other micro-organisms, embedded in a protective layer with entrained debris, attached to a surface. Calorifier - An apparatus used for the transfer of heat to water in a vessel by indirect means, the source of heat being contained within a pipe or coil immersed in the water. Cooling Tower- An apparatus through which warm water is discharged against an air stream; in doing so part of the water is evaporated to saturate the air and this cools the water. The cooler water is usually pumped to a heat exchanger to be reheated and recycled through the tower. Deadleg - Pipes leading to a fitting through which water only passes when there is a draw-off from the fitting. Disinfection - A process which destroys or irreversibly inactivates micro-organisms and reduces their number to a non-hazard level. Legionnaires Disease - A form of pneumonia caused by Legionella bacteria. Legionellae - The genus Legionella belongs to the family Legionellaceae that has over 40 species. These are ubiquitous in the environment and found in a wide spectrum of natural and artificial collections of water. Legionella Pneumophila - One of the causative organisms of Legionnaires disease. Legionellosis - Any illness caused by exposure to Legionella. Pontiac Fever - A disease caused by a species of Legionella, an upper respiratory illness less severe than Legionaires disease. Nutrient - A food source for micro-organisms. Pasteurisation - Heat treatment to destroy micro-organisms usually at high temperature. Ppm - Parts per million: a measure of dissolved substances given as a number of parts there are in a million parts of solvent. Sero-group - A sub-group of the main species. Sentinel taps - For a hot water services the first and last taps on a recirculating system. For cold water systems, the nearest and furthest taps from the storage tank. Page 23 of 24

24 Shunt pump - A circulation pump fitted to hot water services/plant to overcome the temperature stratification of the stored water. Stagnation - The condition where water ceases to flow and is, therefore, liable to microbiological growth. Total viable counts- The total number of culturable bacteria (per volume or area) in a given sample (does not include Legionella). Page 24 of 24