Legionella and Water Hygiene Policy

Introduction

Legionnaires’ disease is a potentially fatal pneumonia caused by legionella bacteria. It is the most well known and serious form of a group of diseases known as legionellosis. Other similar but usually less serious conditions include Pontiac fever and Lochgoilhead fever. Infection is caused by breathing in small droplets of water contaminated by the bacteria. The disease cannot be passed from one person to another. Everyone is potentially susceptible to infection but some people are at higher risk e.g. those over 45 years of age, smokers and heavy drinkers, those suffering from respiratory or kidney disease and people whose immune system is impaired.

Legionella bacteria are common in natural water courses such as rivers and ponds. Since legionella bacteria are widespread in the environment, they may contaminate, proliferate and grow in other water systems such as cooling towers and hot and cold water services. The bacteria thrive at temperatures between 20 deg C and 45 deg C if the conditions are right, e.g. if a supply of nutrients is present such as rust, scale, algae, sediment and other bacteria. Legionella bacteria are killed by high temperatures.

If water droplets are created and dispersed into the atmosphere, then people in the vicinity may be at risk of inhaling the bacteria. To eliminate or reduce the risk, control measures must be in place to prevent the proliferation of the organism in water systems and to minimise the generation of water droplets and aerosols.

Arrangements

Legal requirements

The specific requirements for the control of legionella bacteria in the workplace are provided in The Prevention or Control of Legionellosis, Approved Code of Practice L8, (ISBN 978 0 7176 1772 2), published by the Health & Safety Executive.

The principal requirements include:

• Identifying and assessing sources of risk
• Preparing a scheme (course of action) for preventing or controlling the risk
• Implementing and managing the scheme – appointing a person to be managerially responsible, often referred to as the 'responsible person'
• Maintaining records and checking that what is being done is effective
• Providing training for persons with delegated responsibilities

Compliance with L8 ensures compliance with duties under the Health and Safety at Work Act 1974 and the Control of Substances Hazardous to Health Regulations (COSHH) 2002.

ACoP L8 has been approved by the Health and Safety Commission, with the consent of the Secretary of State. It gives practical advice on how to comply with the law. If you follow the advice, you will be doing enough to comply with the law in respect of those specific matters on which the Code gives advice. You may use alternative methods to those set out in the Code in order to comply with the law. However, the Code has a special legal status. If you are prosecuted for breach of health and safety law and it is proved that you did not follow the relevant provisions of the Code, you will need to show that you have complied with the law in some other way or a Court will find you at fault.

The L8 document also contains guidance issued by the Health and Safety Commission and Executive. Following the guidance is not compulsory and you are free to take other action. But, if you do follow the guidance you will normally be doing enough to comply with the law. Health and Safety inspectors seek to ensure compliance with the law and may refer to this guidance as illustrating good practice.

L8 applies to:

• Hot and cold water systems
• Plant or systems containing water likely to exceed 20°C, which may release aerosols during routine operation or maintenance
• Cooling towers
• Evaporative condensers

This Policy Statement sets out the arrangements for controlling legionella in the University’s water systems, plant and specialist equipment, in accordance with ACoP L8.

Principal Objectives of the Policy

The principal objectives of the legionella and water hygiene policy are:

• To safeguard anyone who may be affected by legionella or similar bacteria within or close to any Dundee University premises
• To ensure an effective management system is in place
• To prevent possible cross contamination between mechanical plant, user equipment and hot and cold water and wholesome water supplies within University premises.

Duty holders and responsibilities

The control and management of legionella in hot and cold water systems is a corporate responsibility and the role of the Statutory Duty Holder rests with the Director of Campus Services.

L8 allows the Duty Holder to obtain assistance from a competent service provider and the University has engaged a specialist water hygiene contractor in this regard.

Division of Responsibilities

The Estates Department is responsible for the safety of the supply of hot and cold water to the outlets, i.e. taps, showers etc and isolation points for water using equipment.

Colleges / Schools are responsible for ensuring the safe use of these water supplies within the areas under their control and as stakeholders, share responsibility with Estates in the prevention of legionella proliferation and cross contamination of water systems.

Estates Department (Estates)

Estates have responsibility for the design, installation and ongoing management and maintenance of the hot and cold water systems within all University of Dundee properties.

Estates will appoint a Responsible Person and deputy Responsible Person(s) as appropriate. The RP / deputy RP`s are charged with implementing a written scheme to control legionella within domestic hot and cold water systems within University buildings. The RP / deputy RP will monitor and review the effectiveness of the scheme.

The main duties of the Estates RP / Deputy RP are to:

• Identify and assess source of risk; e.g. legionella, cross contamination
• Review risk assessments in areas where significant changes occur with a full review every two years
• Review risk assessments and action any recommendations highlighted within
• Prepare a scheme or course of action for preventing or controlling the risk
• Implement and manage the scheme
• Keep records and check that what has been done is effective
• Liaise with College / School RPs to provide assistance and guidance
• Identify training for persons with delegated responsibilities
• Liaise with College / School RPs

a) Legionella Risk Assessment

Estates will take the lead role in carrying out legionella risk assessments for all hot and cold water building services distribution systems within all University of Dundee properties and organise risk assessments for departmental water using equipment connected to the building domestic hot and cold water distribution systems.

b) Design, monitoring and maintenance of hot and cold water systems

Estates are responsible for:

• Ensuring that the design of hot and cold water systems within buildings complies with all relevant legislation
• Ensuring that employed Contractors and in-house staff comply with the written scheme / all aspects of ACoP’s L8
• Monitoring the temperature of hot and cold water supplies in all University of Dundee buildings for which it has direct responsibility and carrying out remedial works if required
• Ensuring the ongoing maintenance of all University of Dundee hot and cold water systems that form part of the building services infrastructure
• Facilitating appropriate safety training courses for all those with responsibilities for compliance with this policy, including Colleges and Schools Responsible Persons
• Endeavouring to ensure full compliance with all aspects of ACoP`s L8

Colleges and Schools

Colleges and Schools have duties under this policy. Each College / School is responsible for the ongoing management of use for departmental water-using equipment and general domestic hot and cold water building distribution systems within the areas that come under their control.

Such systems may include but are not limited to wash hand basins, showers, sinks, humidifiers, autoclaves, catering equipment, pot wash spray flexible hoses, lathes, power wash spray lances, irrigation systems, hose pipes, greenhouse misters – in summary management of all outlets and departmental water using equipment that is connected to the building domestic hot and cold water distribution systems.

a) Colleges and Schools Responsible Person

Each College / School must appoint a Responsible Person. The College / School RP will be responsible for water hygiene associated with general use of domestic hot and cold water systems and water using equipment or systems (departmental equipment / operations/ standard operating procedures). It may also be necessary to appoint deputy RP`s for each sub-division or functional unit. It is the responsibility of the Dean of College / Head of School to make such appointments, as appropriate. If a particular risk is identified, then the RP should ensure that suitable actions are taken to remove the risk or implement effective measures to control the risk. The names of all College / School RP`s and deputy RP`s should be provided to Estates and University Safety Services.

The College / School RP will carry out, or where relevant ensure that deputy RPs carry out the following:

• Identify infrequently used outlets
• Organise and carry out flushing of infrequently used outlets and maintain records
• Identify and schedule all departmental water using equipment
• Seek competent advice
• Liaise with the Estates RP or deputy RP
• Attend organised training for persons with delegated responsibilities
• Attend regular water hygiene meetings organised by the Estates RP

b) Specialist departmental systems or equipment

Where departments possess and operate specialist water systems or equipment that are completely independent of the domestic hot and cold water building distribution supplies, i.e. not connected to the building services infrastructure although require water supplies and therefore may still present a potential legionella exposure risk, then the department must take on the responsibilities of the Duty Holder. In such cases, the College / School RP should contact Estates or the University Safety office for guidance.

c) Risk Assessment

Colleges and Schools are responsible for notifying Estates of any / all water using equipment, systems or activities directly under their control. All departmental equipment permanently connected to the domestic hot and cold and wholesome water (mains cold water) supplies must be identified and risk assessed.

The Estates RP will arrange for such risk assessments to be carried out. The Estates RP will discuss the results of the risk assessment and any remedial actions / control measures requiring to be implemented with the College / School RP.

Specialist advice is available and departments requiring assistance in fulfilling their duties should contact the Estates Department or University Safety Office.

d) Emergency Procedures

If during routine monitoring and maintenance of hot and cold water systems and related equipment, legionella bacteria of a concentration level likely to be hazardous to health is discovered then any systems likely to provide a medium for the spread of infection (e.g. water aerosol spraying equipment) must be immediately shut down.

Control of Legionella

a) The broad requirements of L8 for controlling legionella bacteria in water systems are:

• Appointment of a responsible person (in a managerial rather than technical grade)
• Formal legionella risk assessment with suitable and sufficient documentation of findings, including schematic drawings detailing the water system
• Ongoing review and reassessment of legionella exposure risk
• Development of a risk minimisation programme, a prioritised action plan and a mechanism for escalating remedial work where risk assessment and monitoring data indicate a risk
• Implementation and management of the programme
• Development of formal procedures for inspection, maintenance and disinfection of water systems
• Training of staff
• Maintaining suitable records

b) Risk assessments should be reviewed at least biennially and when they may no longer be valid. For example when significant changes are made to the use of the building or significant changes are made to the water services infrastructure within the building.

c) The Estates Department is responsible for the maintenance, monitoring, treatment, cleaning and disinfection of hot and cold water systems according to the guidance set out in L8 and the risk assessment for each system should detail these arrangements.

d) Where risk assessment identifies a significant risk, the Estates Department will arrange for the system to be disinfected immediately, either thermally or by chemical means. The system will then be monitored to ensure the efficacy of the treatment regime. If necessary, the regime will be modified until the risk of exposure to legionella is reduced to acceptable limits.

Hot and cold water services

a) Water services systems must comply with the Scottish Water Byelaws (2004), BS EN 806 parts 1 – 5, BS 8558 (2011) and any subsequent amendments to these documents.

The Estates Department will endeavour to ensure that only competent contractors are engaged for maintenance, repair, or replacement programmes and that only approved materials are used.

b) Estates will ensure that cold water storage is minimised to avoid stagnation occurring with the storage tank(s). Estates will ensure that suitable measures are in place to protect cold water storage tanks from heat gain and dust ingress. Estates will endeavour to ensure that tank fed cold water distribution systems deliver cold water to the outlet at ≤ 20 deg C.

c) Storage calorifiers and recirculating hot water systems should store hot water at a minimum temperature of 60 deg C and deliver hot water of at least ≥ 50 deg C at sentinel and representative outlets. Estates are responsible for monitoring and recording these temperatures.

d) Where thermostatic mixing valves (TMVs) are installed, these must be sited as close as possible to the point of use. As a general rule TMVs should not serve multiple outlets.

e) All domestic hot and cold water outlets e.g. taps, showers, drip cups, trigger operated spray guns, hose pipes etc must be used regularly; - at least on a weekly basis to prevent potential stagnation of the water supply. Colleges / Schools must identify to Estates any outlets that are used either intermittently or which are under-used and immediately report any faults or problems found with the domestic hot and cold water system. Outlets that are identified by the College / School RP as being under-used, are classified under ACoPs L8 as 'infrequently used outlets'. The College / School RP / deputy RP will ensure that all infrequently used outlets are being flushed to drain for at least five minutes, once a week and records of flushing kept on file.

Flushing of infrequently used outlets is an extremely labour intensive activity and consideration should be given by the College / School for permanent removal of the infrequently used outlet if considered appropriate.

Departmental managers must also appraise Estates of any significant change of use within their department that may adversely impact on the legionella control programme and therefore necessitate a re-risk assessment of the installation.

Emergency showerheads / drench showers and eye wash stations

a) Laboratory showerheads / drench showers

The College / School RP is responsible for ensuring that laboratory showerheads / drench showers are flushed and purged to drain on a weekly basis.

This flushing exercise must ensure aerosols are not being created and that personnel undertaking this task are trained to do so. Detailed records must be kept on file.

b) Laboratory / Departmental emergency eye wash stations

The College / School RP is responsible for ensuring that eye wash stations are flushed and purged to drain on a weekly basis.

This flushing exercise must ensure aerosols are not being created and that personnel undertaking this task are trained to do so. Detailed records must be kept on file.

Humidifiers and spray type air washers

a) The University’s policy has been to replace spray humidifiers and spray air washers with steam humidifiers. Departments who continue to operate such equipment should notify the University Safety Services Office with comprehensive details of equipment still in use.

b) Existing spray humidifiers and spray air washers must be regularly inspected, cleaned, disinfected and maintained by the department.

c) There are currently no ultrasonic humidifiers under the control of Estates. Future installation of such equipment should be discouraged since it introduces a potential risk of legionella exposure, demanding rigorous inspection and maintenance.

d) Where departments continue to use ultrasonic humidifiers as part of their experimental equipment, then it is their responsibility to arrange for inspection and maintenance, to clean and disinfect all wetted parts six monthly, with sampling of the ultrasonic mist for the total viable count (TVC) at three monthly intervals.

Other equipment and activities that create risk

a) Equipment such as water softeners, sprinkler and hose reel systems, lathe or machine tool coolant systems, horticultural misting equipment, fume cupboard water supplies, automatic feeding systems, indoor fountains and water features can also create risk.

b) The department should provide adequate written information to users to enable safe use of the water system(s).

Cooling towers and evaporative condensers (including adiabatic systems)

a) There are no evaporative condensers in the University and none may be newly installed.

b) Adiabatic cooling systems are not permitted in the University.

Training

Estates can arrange training sessions and seminars in conjunction with the University’s specialist water hygiene contractor. College / School RP`s and deputy RP`s should attend, as well as those individuals who are managerially responsible for specialist departmental water using equipment.

Further information relating to training may be obtained from Estates or the University Safety Services Office.

Summary of College / School actions

Departments must ensure that:

a) Suitable regimes are in place for general maintenance, disinfection, cleaning and monitoring of specialised water systems / departmental equipment, and that records are kept.

b) Ensure that personnel who operate and maintain specialised water systems / departmental equipment are suitably trained.

c) Estates are notified and given the opportunity to comment and advise in advance of any intended alteration to the domestic water distribution system(s) prior to works being instructed or commencing.

d) Estates are notified of any hot or cold water outlet which is under-used or used intermittently (infrequently used outlets) so that an appropriate management plan can be discussed and implemented by the College / School.

e) All specialised water systems / departmental equipment connected to water supplies are risk assessed for legionella exposure.

f) Ensure that drinking water chillers are regularly serviced and maintained by the University`s drinking water chiller service provider with records retained on file.

g) Assist Estates to minimise the risk of cross contamination of domestic hot and cold water and wholesome water supplies from water using departmental equipment / specialist equipment. Departments should seek advice and guidance from Estates.

h) The Safety Office is notified, upon receipt of this Policy Statement, with details of air spray washers or spray humidifiers still in operation.