2.1     Background Information on Legionella and Legionnaires Disease

Legionella is the bacterium which causes Legionnaires disease. Of this bacterium,

Legionella pneumophila is one species and is the one most commonly associated with disease outbreaks. Legionnaire’s disease is identified as a pneumonia type of infection of the lower respiratory tract. The infection is most commonly acquired by the inhalation deeply into the lungs of airborne droplets or particles (<5μ) containing viable Legionella. Exposure to Legionella can also cause a short feverish illness without pneumonia known as Pontiac Fever.  Legionella principally affects those who are susceptible due to age (the very young and the very old), illness or immunosuppression.

Research and investigations indicate that the occurrence of Legionella contamination is greatest in water cooling towers, evaporative condensers, hot and cold-water services, water spray humidifiers and air washers, spa baths and pools where water is agitated and recirculated. The contamination from a cooling water tower will cover a far larger area than any other likely source.

Sediment, scale, and organic materials present in water systems can provide nutrients and give protection for Legionella. Legionella have been shown to colonise certain types of water fittings, pipework and materials used in the construction of water systems. The presence of these materials may provide nutrients for Legionella and make eradication difficult. Other organisms in water systems such as bacteria, amoeba and algae can provide a suitable nutrient and habitat in which Legionella can survive and multiply.

The presence of micro-organisms within water systems can provide ideal conditions for Legionella to grow.

Legionella is most likely to proliferate in water systems that operate at a temperature of between 20⁰C and 50⁰C. Human blood temperature of approximately 37⁰C is the ideal temperature for proliferation. Stagnant water within the above temperature range appears to provide ideal conditions to promote colonisation by Legionella.

Legionella will survive at temperatures below 20⁰C but is considered to be in a dormant state with no growth activity. The bacterium does not survive temperatures maintained consistently at 60⁰C or above.

For water samples collected and returned to the laboratory, Legionella pneumophila is recovered by propagation of the organism on a specially supplemented nutrient growth medium. Such samples are normally then incubated at around 37⁰C. It may take up to 7 days for colonies of Legionella to appear. Legionella can be recognised by visual examination of the colonies followed by a number of laboratory techniques to identify species and serogroup.

Legionnaire’s disease is most commonly caused by the inhalation of water droplets contaminated with the Legionella bacteria. It is therefore important that systems susceptible to colonisation by Legionella, and which incorporate a potential means for creating and disseminating water droplets, are identified and the risk they present be assessed.

Water droplets are created in various ways such as spraying, bubbling, and following impact onto hard surfaces. Large drops may be reduced to respirable-size by further impact or evaporation. The smaller particles can persist in the air for long periods and will be carried on air currents.

A water risk assessment (WRA) must be completed for routine system operation and use and also for circumstances such as breakdown, abnormal operation, commissioning, or other unusual circumstances. Once the assessment has been completed a prevention /control strategy can be prepared based on the level of risk.

The Council has appointed accredited Legionella consultants to provide professional services in relation to the identification and management of risks relating to water services (pipe work, taps, showers, mixers, cold-water tanks, hot water cylinders, air conditioning, fire hoses & sprinklers) and has made an assessment of the risks.

The risk assessment takes account of:

• The potential for formation of droplets.

• The condition of the water.

• Hot water temperature.

• Cold water temperature.

• The water turnover rate.

• The susceptibility of persons exposed to droplets.

• The population density exposed to droplets.

The report produced for each site includes the following:

• Survey of all relevant services.

• Plans and schematics of the services.

• Condition of the water services and equipment.

• Assessment of risks.

• Summary of remedial work recommendations.

• A list of routine actions to be taken by specific duty holders at specified intervals.

The following detailed procedures have been drawn up to ensure the risk from Legionella is minimised in Council buildings and is dealt with in accordance with legislative requirements and best practice.

• Buckinghamshire Council has appointed an appropriately qualified Consultant to survey and carry out risk assessments for all Council properties.

• A report containing a risk assessment and list of remedial work required to correct defects has been compiled by the Consultant for each establishment.

• The appointed Consultant has created a web portal which is the primary source of all this information and to which all appropriate staff have access. The Property Team will assess and prioritise any remedial work required, based upon the risk assessment and available funding. This will be a combination of housekeeping measures for which the premises will be responsible and changes in design for which the Council may be responsible, following the established protocols for maintenance responsibilities.

• If you download and keep a hard copy of the information, the Premises Responsible Person or Nominated Legionella Co-ordinator will need to put in place their own management regime, with audit trail, for keeping this copy set of records up to date; Charts to record Temperature and Flushing of Outlets can be found in Appendix 9.

• Headteachers/Managers of establishments must appoint a “Premises Responsible Person” and a “Nominated Legionella Co-ordinator” for each site under their control. (See Appendix 1 for definition).

• The Premises Responsible Person and the Nominated Legionella Co-ordinator are to carry out the duties referred to in the Legionella report. The collected information is to be recorded electronically on the web portal so that the Consultant can review and monitor the information on behalf of Buckinghamshire Council and take appropriate action.

• The Consultant to make monitoring visits to all properties at 6 month and 12 monthly intervals. This will be organised in collaboration with the Property Service Team.

• The Consultant to carry out a risk assessment review of each site at the end of the 5-year contract. This will be organised by the Property Service Team.

The Premises Responsible Person and/or Nominated Legionella Co-ordinator must, after training, take regular readings of water temperatures and carry out the other specified housekeeping duties as recommended in the Legionella report, with the results mad available to the Consultant as mentioned above in 2 Water Hygiene Procedures. This will enable the Legionella risk assessment and monitoring data to be reviewed/updated and identify possible faults at the six-monthly Consultant’s monitoring visits, or earlier should the need arise.

The Consultant will also carry out the following monitoring inspections to conform to Approved Code of Practice and Guidance on Regulations L8

Minor monitoring visit at 6 months from initial survey

• Water temperatures to be checked and recorded at all hot and cold-water outlets.

• Water temperatures to be checked and recorded at calorifiers (hot water tanks) and cold-water storage tanks.

• Changes and alterations to the system checked and recorded.

• Review of control measures.

• Review key personnel and check for any changes.

• Review records of precautions.

• Examination of onsite record keeping.

Major monitoring visit at 12 months from initial survey

• Water temperatures to be checked and recorded at all hot and cold-water outlets.

• Water temperatures to be checked and recorded at calorifiers and cold-water storage tanks.

• Tanks and calorifiers to be checked for the presence of organic material, ill-fitting, loose, or corroded covers.

• Accessible pipe work and lagging will be checked for damage.

• Condensate trays and pipes checked for water accumulation.

• Water samples shall be taken from the cold-water storage tank and the furthest outlet from the calorifier outlet or nearest tap, the return supply and from the base of the calorifier for testing.

• Changes and alterations to the system checked and recorded.

• Review of control measures.

• Review key personnel and check for any changes.

• Review records of precautions.

• Review and examination of onsite record keeping.

The above will be repeated at 6 and 12 monthly intervals throughout the period of the 5-year contract. The Consultant’s checks at 6 and 12 months are not intended to replace those carried out by the Premises Responsible Person/Nominated Legionella Coordinator but are in addition to them.

Premises managers should, as part of their regular health and safety inspections, review the web-based portal and check that it is being used in accordance with the prescribed procedures, recording that they have done so.

The record of the Legionella water risk assessment is a living document that must be reviewed to ensure it remains up to date. The assessment will be regularly reviewed as stated above, however it will also need to be reviewed specifically whenever there is reason to suspect it is no longer valid. An indication of when to review the assessment and what to consider should be recorded, is as follows:

• If there are changes to the water system or its use.

• If there are changes to the use of the building in which the water system is installed.

• If there is new information about risks or control measures.

• The results of checks indicate that the control measures are no longer effective.

• There are changes to key personnel on site for example the Premises Responsible Person or the Legionella Co-ordinator.

• A case of legionnaires’ disease or legionellosis is associated with the system.

As noted above, risks have been identified and assessed and a scheme has been prepared for preventing or controlling those risks at each establishment. The reports by the Consultant include recommendations for improvements which the Property Service Team will consider and where necessary arrange the removal of or improvement to those parts of the installation that could harbour infection.

Remedial work will be prioritised within available budgets and actioned by the Property Service Team as detailed above in 3 Water Hygiene Procedures. Where work cannot be actioned, control measures (housekeeping) will need to be put in place. These control measures may include such things as the weekly running of taps or showers at the end of pipe runs that are infrequently used, in order to flush out stagnant water.

Any concerns about possible contamination or abnormal temperature readings not covered by any of the above should be made known to the Property Service Team as soon as they occur.

In order to ensure that the Premises Responsible Person and the Nominated Legionella Co-ordinator are competent to carry out their tasks in relation to the Legionella Policy these persons must attend a half day training session presented by the Council’s Health and Safety Team. Details of these courses are available from the Health and safety training pages or contact handstraining@buckinghamshire.gov.uk

It is likely that the first notification of any outbreak involving a BC property would come from an BC Council Environmental Health Officer (EHO), Health and Safety Executive (HSE.) or the Police. Such a body would instigate their own investigation, usually in collaboration with BC Head of Health & Safety.

• The Head of Health & Safety, in collaboration with the Director of Property and Assets and the Head of Property Services will co-ordinate the Council’s response to the outcomes of that investigation. Appropriate members of the Health and Safety Team will take reports to the Corporate Health Safety and Wellbeing Committee (CHSWC) and Local Workforce Matters Meetings. Although unlikely, in the event of an incident occurring, the following emergency procedures must be implemented:
• An immediate evacuation and isolation of the contaminated area. The area should be locked-off, with warning signs posted. No re-entry should be allowed for any reason until the area has been declared safe by the Director of Property and Assets and the Head of Property Services
• The Property Service Team will be alerted, and appropriate de-contamination procedures instigated.
• Where building users (employees, clients, pupils, visitors) may have been contaminated, advice will be taken from the Council’s Occupational Health provider and / or the Buckinghamshire Health Protection Agency/Public Health England, Thames Valley Health Protection Team (South East) (Tel.0344 225 3861 option 1 to 4 depending on area, then option 1);
• A copy of the incident report for those affected by the exposure will be retained by the Head of Health and Safety and the Council Insurance Manager.

Leased-in Building

Where buildings are not owned or maintained by Buckinghamshire Council, but their use is under the control of officers employed by the Authority, (e.g. office building, Group Home, Leisure Centres), the Head of Property Services will undertake the following:

• Obtain from the owner of the building a copy of the water risk assessment and the risk management procedures in place.

• Assess whether the management of Legionella risk complies with Council standards.

• Ensure that Service Areas whose employees are in control of such buildings are made aware of the management procedures in place and their part in that procedure, where applicable.

Service Areas in control of buildings which are hired/leased-in will be responsible for ensuring the Property Team is notified of any currently hired or leased buildings or any changes to the building portfolio.  Where the terms of any hiring agreement or lease require clarification as to the Service Areas responsibilities the Head of Strategic Assets will carry this out with legal support where necessary.

Where the building owner has inadequate or no Legionella control procedures in place, or where BC is responsible for the maintenance of the property, the Service Area will be responsible for appointing appropriate staff to the roles required under this policy to manage the controls imposed by BC. Where the survey information is inadequate or missing, then the Head of Property Services will ensure adequate surveys take place. With this information Service Areas should ensure that Officers in charge of hired/leased buildings are fully conversant with this policy and procedures.

Where the landlord retains maintenance responsibilities for common/shared areas, the landlord retains responsibility for the management of Legionella in those areas.

Where shared use of a building occurs, the principal/major user will be responsible for the management of the Legionella for that site, and for ensuring all other users are aware of and comply with this policy’s requirements.

Leased-out buildings

Where buildings are owned but not used or occupied by the Council, the body responsible for implementing this policy (the occupier) shall be identified by the terms of the lease/tenancy or similar agreement.

Agricultural Estate

In the case of the Agricultural Estate, the Council will, through its external Consultants and Managing Agents, implement this policy by surveying all buildings, including those owned by the tenant, and producing a management plan for each farm or holding. This management plan will only apply to buildings owned by the Council.

Buildings Owned by Tenants

With regard to subsidiary buildings owned by the agricultural tenant, the results of the surveys will be forwarded to the tenant with a covering letter drawing the tenant’s attention to the aforementioned regulations and reminding the tenant of the obligations contained therein.

Investment Properties

  The Council’s Investment Properties comprise a mix of single tenanted and multi-tenanted investments. Where properties are single let the body responsible for implementing this policy (the occupier) shall be identified by the terms of the lease/tenancy or similar agreement.  Where properties are multi-tenanted the Council will implement this policy via retained managing agents under the control of the Head of Strategic Assets.

Appendix 1

Glossary of Terms used

Centrally held records - The records currently held by the Property Service
Team on behalf of the Council.

CHSWC - Corporate Health Safety & Wellbeing Committee

Duty Holder - This is a shared role. At a corporate level it is the Chief Executive Officer. At site level it is the person with overall responsibility for managing the premises and systems on a site.

H.S.C. - Health and Safety Commission

H.S.E. - Health and Safety Executive

Nominated Legionella Co-ordinator - Person nominated by the Premises Responsible Person to carry out temperature checks, record keeping etc.

Personal Protective Equipment (PPE) - Includes overalls, gloves, headwear, footwear, respiratory equipment.

Premises Responsible Person - Person (Duty Holder) who is in control of premises or systems and is the person on whom the statutory duty falls at site level. This person should be a manager or have similar status and authority and is responsible for ensuring that the Nominated Legionella Co-ordinator carries out their duties.

Property Service Team - The team within the Planning Growth and Sustainability portfolio at Buckinghamshire Council with responsibility for the day-to-day management of the Legionella policy and remedial works.

UKAS accredited laboratory - A laboratory which is accredited by the UK Accreditation Service.

WRA - Water risk assessment

Appendix 2

Relevant Legislation, Codes of Practice etc. (not exhaustive)

Legislation

Health and Safety at Work, etc. Act 1974

Chemicals (Hazard Information and Packaging for Supply) Regulations 2009

The Personal Protective Equipment Regulations 2002

The Personal Protective Equipment at Work Regulations 1992 (as amended)

CDM Legislation Construction (Design & Management) Regulations 2015

Control of Substances Hazardous to Health Regulations 2002 (Amended 2004)

The Water Supply (Water Quality) Regulations 2016

The Private Water Supplies (England) Regulations 2016

Water Act 2014

H.S.C. Approved Codes of Practice

Legionnaires’ disease the control of Legionella in Water Systems Approved Code of Practice and Guidance on Regulations L8        

 H.S.C. Technical Guidance

HSG274 Part 1 Legionnaires Disease the Control of Legionella Bacteria in Evaporative Cooling Systems 2013

 HSG247 Part 2:  Legionnaires Disease The control of legionella bacteria in hot and cold water 2014

HSG274 Part 3 Legionnaires’ disease: The Control of Legionella Bacteria in other Risk Systems 2013

Appendix 3

Legionella Co-ordinating Officers

The current Council Legionella Co-ordinating Officers from whom advice can be obtained are:

• John Collins RIBA – Head of Property Services, Property Service Team,

• Matt Hayward MRICS –Head of Planned Maintenance and Projects, Property Service Team.

• George Thompson – Head of Reactive maintenance and Contracts, Property Service Team.

• Peter Halsey – Compliance Officer, Property Team, Property Service Team.

• Mark Hunt – Reactive maintenance and Contracts Manager, Property Service Team.

Appendix 4

Checklist for Hot & Cold Water Systems

The frequency of inspecting and monitoring the hot and cold water systems will depend on their complexity and the susceptibility of those likely to use the water. However, most Legionella assessment will be reviewed on a five-yearly basis. The risk assessment should define the frequency of inspection and monitoring depending on the type of use and user particularly where there are adjustments made by the assessor to take account of local needs. 

Outlet flushing chart (PDF Download)

Outlet temperature chart (PDF Download)

Appendix 5

Important Temperatures to Note

Less than 20 Degrees Celsius: Legionella remains dormant

25-45 Degrees Celsius: Legionella growth likely

32-42 Degrees Celsius: Optimum growth conditions for Legionella

Above 45-50 degrees Celsius: Legionella can survive but will not multiply

Above 50 Degrees Celsius: 90% of Legionella bacteria die within 80-124 min

Above 60 degrees Celsius: Legionella bacteria dies in 2 min

Above 70 Degrees Celsius: Legionella bacteria dies instantly

With this in mind when referring to logs you should expect to ideally see temperatures of <20 or >50 Degrees Celsius

Appendix 6

Useful Contacts

For general advice:

• Health & Safety Team via the Health and Safety Mailbox healthandsafety@buckscc.gov.uk

If the matter is urgent it should be reported immediately to the Health and Safety Team 01296 674412

In the case of routine water hygiene matters you should report any issues to the Buckinghamshire Council Property team via the Property Service Mailbox propertyservice@buckscc.gov.ukFor Occupational Health advice, in the first instance contact your Human Resources Officer.

External sources of Information:

Health and Safety Executive:
Website: www.hse.gov.uk

 

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