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Minimise risk of Legionella with new published guidance

Control of Legionella in water systems is an ongoing concern and especially following the outbreaks of Legionnaires' disease in Edinburgh and Stoke last year. The Chartered Institution of Building Services Engineers (CIBSE) has published a new Guide TM13: Minimising the risk of Legionnaires' disease to set authoritative standards to help reduce risk and provide further understanding on control measures.

Legionella bacteria are commonly found in sources of water, such as rivers and lakes, but can also contaminate building water systems and services (domestic hot and cold water, cooling towers, spa pools, etc). If in these systems the bacteria are allowed to multiply and then become released into the air in water droplets, they can pose a serious problem.

Large buildings, such as hotels, hospitals, museums and office blocks, are more vulnerable to Legionella contamination because they have larger, more complex water supply systems in which the bacteria can quickly spread*.

Greg Davies, who chaired the work group for TM13 comments: "The guidance has been revised and updated to reflect the legal, environmental and technological advancements we have seen over the last decade. The significant advantage of this document is it contains the level of advice needed to support those responsible for managing and maintaining water systems and services, for minimising the risks with Legionella as well as how to demonstrate proactive control."

In the UK, Legionella management is primarily driven through The HSE Legionnaires' disease - the control of legionella bacteria in water systems Approved Code of Practice and Guidance L8 (HSE, 2000). TM13 will help to meet these requirements. The Guide is aimed at practitioners involved with the design, installation, commissioning, operation or maintenance procedures of water systems within a building.

The engineering of systems is important to maintain efficient safety but when managerial and operational procedures fail, this will also increase risk. The Guide aims to address such issues and help encourage an overall effective approach to minimising risk.

To obtain a copy of TM13, please visit