Proposed HTM 04-01 Updates (2026): New SHTM 04-01 Guidance Explained
The proposed changes to HTM 04-01 represent one of the most significant developments in healthcare water safety guidance for many years. While the public consultation period for the revised document is now closed, the direction of travel is becoming increasingly clear. If adopted, the new framework will introduce a more consistent approach across all four UK nations, strengthen governance, broaden the scope of water safety management, and provide clearer guidance for those responsible for designing, operating and maintaining healthcare water systems.
In this article, our expert healthcare team examine the latest proposals for the new HTM 04-01, including the planned expansion from four parts to a seven-part water safety system, the key changes to existing guidance, and the introduction of entirely new sections covering areas such as disinfection, filtration, chloramination and operational procedures. We also share our observations on what these changes are likely to mean in practice for Water Safety Groups, Authorised Persons, Responsible Persons and healthcare estates teams as they prepare for the next generation of healthcare water safety guidance.
A version of this article reviewing the proposed updates to HTM 04-01 and the new SHTM 04-01 guidance for healthcare water safety first appeared in Legionella Control International’s newsletter. To get it in your inbox, sign up here.
What is HTM/SHTM 04-01?
HTM 04-01 (Health Technical Memorandum 04-01) is NHS Englands guidance that sets out best practice for the safe design, operation and management of water systems in healthcare premises to reduce the risk of Legionella and other waterborne pathogens. SHTM (Scottish Health Technical Memorandum 04-01) is the official guidance covering NHS and healthcare premises in Scotland.
What is changing in HTM 04-01?
It’s not unusual for Health Technical Memoranda to receive occasional updates, as new information becomes available. Yet we could be about to see the biggest change yet made to HTM 04-01: Safe water in healthcare premises.
A new UK-wide SHTM 04-01 framework
It has been proposed that the current HTM 04-01 document is changed to become a bigger seven-part water safety system applicable across the UK, suggested as SHTM 04-01. At present, England and Wales have a separate version to the one used in Scotland. This will keep guidance uniform throughout all the UK nations, including Northern Ireland.
Expansion from four parts to seven
Additionally, the document will increase in size. Currently, HTM 04-01 runs to four parts. These comprise Parts A, B, and C, with the additional fourth part, D08, covering guidance relating to thermostatic mixing valves (TMVs) in healthcare. The new water safety system, currently being drafted, looks set to expand into seven parts from A to G.
To be clear, the proposals are currently under consideration having been through a public consultation process which is now closed. Therefore, any potential changes listed here could change again before the final document is drafted and confirmed. We’ll keep you up to date on any further changes or updates that come to light.
Examining the changes to Parts A, B, and C of the current HTM 04-01 guidance
HTM 04-01 Part A – Design, installation and commissioning
Part A currently covers the design, installation, and commissioning of a water system. Proposals cover the expansion of this Part, covering above-ground drainage and water consumption. It will also contain more detailed advice on the installation and commissioning of a water system, along with advice on materials used for this purpose.
HTM 04-01 Part B – Operational management
Part B currently covers operational management of a safe hot and cold water system. The new version will expand to include an updated remit for the Water Safety Group, NTM details, and a greater emphasis on governance, records, competency, and training.
HTM 04-01 Part C – Microbiological testing
Part C currently covers Pseudomonas Aeruginosa and how to manage the risk in augmented care units. The new version provides extensive advice on microbiological testing, including that for Pseudomonas Aeruginosa. The document will highlight sampling and investigation with an eye on better integration in water safety.
Healthcare TMV performance specification
The current D08 supplement for TMVs will become the Healthcare TMV Performance Specification. This is intended to cover risk controls, procurement topics, and maintenance specifications. The changes are less significant than those seen in Parts A, B, and C, yet still important to consider.
New sections proposed for SHTM 04-01
Next, we come to the proposed new parts of the update – D, E, F, and G – which have no direct part in the current HTM 04-01 document. We’ll go through those in turn below to offer further details on each.
Part D: Disinfection of domestic water systems
The first new addition to the document will provide clearer decision-making regarding disinfection and verification of the process.
Part E: Alternative materials and filtration
This is intended to cover filtration governance and the requirement for stronger evidential requirements for products and materials used.
Part F: Chloramination of water supplies
If chloramination is used as part of a water safety plan (WSP), this section will provide further insight into the process and its requirements.
Part G: Operational procedures and exemplar Water Safety Plan
In our opinion this is one of the most important alterations proposed – it supplies operators with templates and a structure for procedures that must be followed.
What do the proposed HTM 04-01 changes mean in practice?
As healthcare water safety specialists we believe this new approach will be far simpler and an advantage to have consistent guidelines and processes throughout all four nations in the UK. According to what we currently know, the final draft will have nation-specific references where required.
Stronger governance and Water Safety Groups
However, in cases where operators are responsible for multiple sites in different parts of the UK, the new seven-part document should make it much easier to consistently follow guidance at all sites. The inclusion of nation-specific references will help in this respect.
A greater focus on evidence and compliance
We’ve also noted the strengthening of Water Safety Group authority, along with the approach to a live Water Safety Plan document (rather than a static document) and Written Scheme evidence.
Above-ground drainage joins the water safety framework
Having read the proposed changes, we’ve noticed that additions are equally as important as increasing the scope in areas already covered by HTM 04-01. For example, above-ground drainage will now be covered and included in the new Part A.
Wider coverage of waterborne pathogens
Meanwhile, Legionella and Pseudomonas Aeruginosa will no longer be the focus of the new guidance. All waterborne pathogens will be covered, to ensure nothing is missed when considering the risks posed by a hot and cold water system, including provisions to cover Non-Tuberculous Mycobacteria (NTM), previously addressed in estate technical bulletins.
In some cases, for example with microbiological testing, current guidance will be moved to another part of the new document. Pseudomonas testing currently sits in the addendum in Part C, whereas it will now be moved within Part C to sit alongside TVC guidance.
Easier compliance across the UK
We also think that the new parts of the document will help WSGs locate pertinent information more quickly. For example, concerns including sustainable development and energy conservation will become more visible than before to reflect the changing needs of our planet.
Strengthening the role of the Water Safety Group
We can see that the proposed new HTM 04-01 version is not merely a case of bringing everything together in one place to cater to all four corners of the UK. Significant editing will occur to make the document more accessible, so that it will become easier to find relevant information about disinfection, control measures, and many other aspects of water safety in healthcare environments.
And that, of course, is the reason why this major change is taking place. It should improve resilience as the document will guide and support WSGs to take the proper actions to ensure they meet all relevant compliance requirements. It also covers everything from projects and refurbishments to ongoing microbiological testing, ensuring there are no gaps in water safety at any point.
The main takeaway here is that the proposed changes should bring all the current guidelines into one integrated water safety management system. Operators who are responsible for a water system should ensure they strengthen their current governance and evidential procedures to ensure compliance with the new document when it is launched.
We will update you on further information as we get it once the new SHTM 04-01 document is complete.
HTM 04-01 draft change report available from Legionella Control International – Request your copy today
Our healthcare water safety specialists have carried out a comprehensive clause-by-clause review of the draft SHTM 04-01 consultation documents, comparing them with the current HTM 04-01 guidance and highlighting the practical implications for healthcare providers. The report identifies the key technical, governance and operational changes, together with recommended actions to help organisations prepare for implementation. If you would like a copy of our HTM 04-01 / SHTM 04-01 Draft Change Report, please get in touch and we’ll be happy to provide it on request.
Looking ahead
While the proposed changes to HTM 04-01 are not yet final, they provide a clear indication of how healthcare water safety is evolving. The emphasis is shifting beyond individual compliance tasks towards a more integrated approach that places greater importance on governance, evidence, competency and the ongoing management of risk. For those responsible for healthcare water systems, now is a good opportunity to review existing Water Safety Plans, governance arrangements and record-keeping processes so that any future transition can be managed with confidence.
As with any major update to national guidance, the final document may differ from the current proposals following consultation. However, the overall direction is unlikely to change significantly. We will continue to monitor developments and provide updates as more information becomes available. In the meantime, understanding the proposed changes will help Water Safety Groups, Responsible Persons and healthcare estates teams prepare for the next generation of HTM 04-01 and continue delivering safe, compliant water systems for patients, staff and visitors alike.
If you’re responsible for managing water safety within a healthcare organisation and would like to understand how the proposed HTM 04-01 changes could affect your buildings, our healthcare water safety specialists can help. We can review your current Water Safety Plan, governance arrangements and compliance procedures, carry out a gap assessment against the proposed guidance, and provide practical advice to help your organisation prepare for the transition to the new SHTM 04-01 framework with confidence.
