Legionella Control at the University of Sheffield: Awareness and Preventive Measures

1. Legionella control in the University of SheffieldLegionella Awareness for Departmental representatives

2. What is Legionella? • A naturally occurring bacterium • Found in most water systems • Often present in mains water • Easily colonises most domestic water systems – hot and cold

3. Requirements for Growth? • Optimum temperature range of 20 - 45 ⁰C • Food source (other bacteria & sediments) • Prefers stagnant conditions

4. Route of Infection? • Primarily through inhalation of aerosols, fine droplets & mists • Can be contracted by choking on contaminated water • Statistically most susceptible - 50 to 70 year olds - Males - Smokers

5. How big a risk?

6. Legionnaire’s Disease • Potentially fatal form of pneumonia – 5-30% fatality rate • 200-300 cases of infection in England & Wales annually • Incubation period 2-10 days - typically 3-6days • Legionella pneumophila – 23 sub types • HSE view Legionnaire's Disease as “preventable” assuming management failure!

7. Legionnaire's Disease

8. Legislation • The Health and Safety at Work etc Act 1974 • Management of Health & Safety at Work Regulations 1999 • COSHH 2002 • ACOP L8 (see front cover)

9. L8 Guide to Successful Control Requires: • Management regime in place • Risk Assessments • Control regime • Maintenance and upgrade • Review

10. Risk Assessments should: • Identify & quantify relevant wet systems plus equipment holding / circulating water • Assess potential for Legionella growth • Identify who is at risk • Assess the potential for bacterial transfer • Quantify and prioritise the risks • Determine suitable means of control

11. UoS Responsibilities 1 • Statutory Duty Holder who is ultimately responsible – Registrar & Secretary • Appointed Responsible Person for day to day management – Director of Estates • Deputy Responsible Person to cover holidays and illness – Head of Engineering Operations • Responsibility cannot be delegated

12. UoS Responsibilities 2 • Policy for the Control of Legionella bacteria • Management structure in place with Contractors charged with carrying out: - • Legionella Risk assessments of all buildings • Treatment of water assets where required • Sampling and analysis of water systems • Remedial works incl. removing “dead-legs” • 5 Zones - Engineers managing Contractors

13. Current Position • Current regime in place for > 2 years • 95% buildings assessed (some low risk o/s) • Current costs ~ £250,000 pa • Monitoring of sample results on-line • Legionella Procedures Manual in place • Legionella Control Steering Group – 3 meetings per year chaired by Prof R F Jackson • Policy and Procedures on Safety Services website

14. Typical Systems at Risk • Cooling Towers • Domestic hot & cold water systems • Water features incl. ornamental fountains • Equipment producing aerosols, mists or droplets from stored water sources including showers & humidifiers • Equipment holding / circulating water at 20 - 45⁰ C

15. Examples of lab & workshop equipment • Water tanks & baths • Spray taps • Water recirculation systems for cooling • Rarely used taps & showers (even at home) • Misting equipment • Dentistry tools • Oil / water emulsions for lubricating lathes • Mobile AC equipment with water

16. Controlling Legionella bacteria • Temperature monitoring • Controlled release of water spray • Avoid temp. conditions 20 - 45⁰ C • Avoid water stagnation - empty & clean regularly • Avoid materials which harbour bacteria • Maintain cleanliness of spray outlets • Water treatment where necessary • Ensure correct & safe operation of system • Flushing regime for rarely-used outlets

17. What Departments need to do - 1 • Identify a Nominated Person to help you manage Legionella risks in your Department • Identify & record all : - • water-containing equipment which operates in the temperature range 20-45⁰C • all rarely-used taps & showers • all equipment supplied from stored water sources producing sprays, mists or aerosols • Assess the risk of Legionella growth in each

18. What Departments need to do - 2 • Check Legionella Procedures Manual for information of the management of specific items of laboratory equipment • If your equipment is not listed, determine the best means of reducing Legionella risks – if needed, contact Department of Estates for help • Consider which treatment options are the most appropriate from the next slide

19. Treatment / remedial options • Monitor temperatures; 20-45⁰C = risk range • Every 2 weeks - heat water to 60⁰C for 5 mins • Add disinfectants / Chloros as advised • Empty out the water system, thoroughly clean & refill with fresh water every month • Clean & disinfect spray heads every month • Flush rarely-used outlets weekly • Arrange with Estates for removal of “dead-legs” • Arrange with Estates for samples to be taken if risk exists (sampling is NOT a control measure – it takes 10 days for results to be sent through – it monitors whether your controls work)

20. Next step • Record all actions taken and results received. • Review the efficacy of the treatment regime by checking the results of analyses received • Re-assess the risk assessment if there are any changes to the operating parameters or the system layout

21. Drinking water coolers • 2 types generally available: • Using large bottles of mineral water • Plumbed-in units • Legionella is not reported to be a problem with water bottle coolers, usually work outside “critical temperature range”, • 1 reported instance of Legionella bacteria being isolated from Activated Carbon filters in a plumbed-in unit in New Zealand – replace as recommended by manufacturer.

22. We hope you found this information useful!