• Online training login
t: 0330 223 36 86     e: [email protected]
Legionella Control International
  • Home
  • Services
  • Knowledge
  • Legionnaires
  • About
  • Contact
  • Click to open the search input field Click to open the search input field Search
  • Menu Menu
You are here: / Home / Knowledge / Compliance / HSG274 Part 2: Legionella Bacteria in Hot & Cold Water Systems

HSG274 Part 2 Overview: Legionella bacteria in hot & cold water systems

HSG274 Part 2Important changes to the way the UK’s Health & Safety Executive deal with the control of legionella bacteria and Legionnaires’ disease in HOT & COLD WATER SYSTEMS have now been published in the form of their Health & Safety Guidance HSG274 Part 2 … find out how they affect you with our detailed review and forthcoming breakfast briefings.

The formal system of legionella control in the UK now comprises the HSE’s ACOP L8 (4th edition) and HSG274 which is split into three parts:

  • Part 1 – cooling water systems.
  • Part 2 – hot and cold water systems – recently published April 2014.
  • Part 3 – other risk systems.

Whay are Hot & Cold Water Systems Important?

Hot and cold water systems, covered by the recently published HSG274 Part 2, are by far the most common form of water system that can potentially create a legionella risk and so these changes are likely to affect you, your staff and your organisation. It is therefore very important that you understand the changes and adjust your legionella risk management systems to remain fully compliant with the law.

The latest edition of the HSE’s HSG274 Part 2 can be ordered direct from the HSE website if you require a hard copy, or downloaded here…

  • Download a free copy of the HSE’s HSG 274 Part 2 here

10 Key Points from HSG274 Part 2 & what You Need to Know

Our legionella experts have now conducted a detailed review of the new HSG274 Part 2 (Hot & Cold Water) and we have summarised 10 key points:

1. HSG274 Part 2, the guidance covering hot and cold water systems has now increased significantly from 15 to 58 pages… a big increase by any standards. Our teams are now advising clients on what they need to do to remain compliant, and expediting the implementation of any changes required.

2. All risk assessments should now consider both the relative risks associated with legionella bacteria and scalding from hot water. A good understanding of the process of thermal disinfection is now also essential to complete a competent risk assessment.

3. There is now significantly more information covering water system engineering design, including:

  • Calorifiers attached to solar heating systems.
  • Expansion vessels.
  • Point of use water heaters and combination water heaters.
  • Clarification on what is a “sentinel” outlet on large multi-loop systems.
  • There is also a simple definition of a low risk system.

4. New Section: “Residential accommodation: Landlords and shared premises”. This new section gives guidance on how to risk assess and control both domestic and commercial tenanted properties. It is essential that property owners, landlords and tenants understand this new section.

5. New Section: “Special considerations for healthcare and care homes”. The guidance gives new information on those special considerations where there are susceptible individuals, including revised guidance on acceptable levels of legionella bacteria in water systems. Our experts are already advising senior health and safety teams and facilities operators in the healthcare sector on the new rules to help them to maintain their compliance status.

5. Commissioning of new buildings has in the past resulted in significant legionella growth. There is now a significant section devoted to this topic which includes guidance when “mothballing” water systems for times of non-use. This is an important area for builders, developers and other owners of property and one that needs careful consideration.

7. Potential problems are highlighted for hot water systems with secondary and tertiary loops; systems that are prevalent in hospitals and healthcare facilities. The guidance also introduces new recommended requirements for routine monitoring.

8. New routine monitoring recommendations are now included, including point of use heaters, combination heaters, TMV’s and others. Additional routine monitoring tasks and KPI’s will be required as a result.

9. Significantly increased section on the use and control of chemical water treatments and biocide systems. Our teams are able to advise in detail on this increased guidance.

10. Appendices included in the new guidance define much broader requirements for the risk assessment and written control scheme including the need for incident planning. Several of our legionella experts are incident planning specialists and advise on the development, implementation and management of such plans.

These issues and more will be covered in greater detail at our breakfast briefings.

Additionally, if you are interested in some further reading a copy of the full HSG274 Part 2 is available to download at the bottom of this page.

Breakfast briefings – Get up to Speed Quickly

To help duty holders, health and safety managers, business owners and those responsible for the management of risk systems understand these changes and ensure their legionella risk management systems and procedures remain compliant with the law we will be presenting a second series of concise breakfast briefings at a number of central locations… breakfast briefings.

More information

More information can be obtained from our experts at Legionella Control International, call us today on 0330 223 36 86 or get in touch here … contact us

Free downloads

To download your complimentary copy (full version) of the HSE’s new HSG274 Part 2 please use the following web link:

  • HSG274 – Part 2 >>

Other downloads

  • ACOP L8 – latest edition >>
  • HSG274 – Part 1 >>
  • HSG274 – Part 3 >>

If you are unable to download the documents here call us today on 0330 223 36 86 or get in touch here … contact us

Search Search

Expert resources…

  • Legionella & other pathogens
  • Regulatory compliance
  • Expert guidance
  • International
  • Legionnaires’ disease
  • Legionella training
  • Glossary of terms
  • FAQ
  • News

REVIEWS

4.8
Legionella Control International is rated 4.8 out of 5 stars (based on 182 customer reviews)
Read our reviews

Get in touch...

Legionella Control International
Warren Bruce Court
Warren Bruce Road
Manchester M17 1LB
United Kingdom

Manchester: +44 (0) 161 877 05 86
London: +44 (0) 203 637 47 48
Email: [email protected]

Legionella newsletter...

A simple and convenient way of keeping up to date with the latest Legionella news, new legislation, best practice, R&D and much more…

Useful downloads…

  • HSE ACOP L8 – Control of Legionella
  • HSG274 Part 1 – Evaporative Cooling
  • HSG274 Part 2 – Hot & Cold
  • HSG274 Part 3 – Other Risks
  • Positive Legionella Tests – What To Do?
  • HSG282 – Spa Pools
  • Legionnaires’ – Duty Holders Guide
  • Health & Safety – Care Homes
  • Scalding Risks – Health & Social Care
            © Copyright 2026 - Legionella Control International Ltd.
  • Link to X
  • Link to Facebook
  • Link to LinkedIn
  • Home
  • About
  • Contact
  • FAQ
  • Disclaimer
  • Privacy
  • Modern Slavery
  • Reviews
  • Sitemap
Link to: Legionella Software for Streamlined Risk Management Link to: Legionella Software for Streamlined Risk Management Legionella Software for Streamlined Risk Managementlegionella logbook software Link to: HSG274 Part 2 Breakfast Briefings… What you Need to Know Link to: HSG274 Part 2 Breakfast Briefings… What you Need to Know hsg274 part2 hot and cold water breakfast briefingsHSG274 Part 2 Breakfast Briefings… What you Need to Know
Scroll to top Scroll to top Scroll to top

This site uses cookies. By continuing to browse the site, you are agreeing to our use of cookies.

OKLearn more

Cookie and Privacy Settings



How we use cookies

We may request cookies to be set on your device. We use cookies to let us know when you visit our websites, how you interact with us, to enrich your user experience, and to customize your relationship with our website.

Click on the different category headings to find out more. You can also change some of your preferences. Note that blocking some types of cookies may impact your experience on our websites and the services we are able to offer.

Essential Website Cookies

These cookies are strictly necessary to provide you with services available through our website and to use some of its features.

Because these cookies are strictly necessary to deliver the website, refusing them will have impact how our site functions. You always can block or delete cookies by changing your browser settings and force blocking all cookies on this website. But this will always prompt you to accept/refuse cookies when revisiting our site.

We fully respect if you want to refuse cookies but to avoid asking you again and again kindly allow us to store a cookie for that. You are free to opt out any time or opt in for other cookies to get a better experience. If you refuse cookies we will remove all set cookies in our domain.

We provide you with a list of stored cookies on your computer in our domain so you can check what we stored. Due to security reasons we are not able to show or modify cookies from other domains. You can check these in your browser security settings.

Google Analytics Cookies

These cookies collect information that is used either in aggregate form to help us understand how our website is being used or how effective our marketing campaigns are, or to help us customize our website and application for you in order to enhance your experience.

If you do not want that we track your visit to our site you can disable tracking in your browser here:

Other external services

We also use different external services like Google Webfonts, Google Maps, and external Video providers. Since these providers may collect personal data like your IP address we allow you to block them here. Please be aware that this might heavily reduce the functionality and appearance of our site. Changes will take effect once you reload the page.

Google Webfont Settings:

Google Map Settings:

Google reCaptcha Settings:

Vimeo and Youtube video embeds:

Other cookies

The following cookies are also needed - You can choose if you want to allow them:

    Download our Legionella Risk Assessment Checklist for business owners, landlords, property managers and health and safety specialists and start managing your legionella risk today.