Legionella control in the University of Sheffield Legionella Awareness for Departmental representatives

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

Requirements for Growth? Optimum temperature range of ⁰C Food source (other bacteria & sediments) Prefers stagnant conditions

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

How big a risk?

Legionnaire’s Disease Potentially fatal form of pneumonia – 5-30% fatality rate 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!

Legionnaire's Disease

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)

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

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

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

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

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

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 ⁰ C

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

Controlling Legionella bacteria Temperature monitoring Controlled release of water spray Avoid temp. conditions ⁰ 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

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

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

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)

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

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.

We hope you found this information useful!