How Hygienic Water Networks Keep Patients Safe

Facilities designed to be visited or occupied by people who are extra sensitive to the effects of bacteria and contamination need to pay careful attention to several design and maintenance factors to provide a safe environment with optimised hygiene levels.


In all buildings such as hospitals, care homes and healthcare facilities, it’s important that this focus extends beyond the most visible parts of the site – like the wards, surgeries and waiting rooms – and is equally concentrated on the more obscure sections of the building. This level of hygiene awareness is required as these harder-to-reach, less-frequently-seen areas can be prime places for bacteria and contaminants to accumulate out of sight.

This need for hygiene control is especially true of the water system, which needs to supply clean and safe water consistently. For healthcare facilities, this can be tricky. Most have extensive water systems which are likely to include not only a large number of hand-washing stations but also aerosol-producing devices – including cooling towers, dehumidifiers and shower outlets as well as equipment unique to the sector, such as respiratory therapy equipment.

Legionella and the spread of bacteria

An unhygienic water network can lead to a long list of issues for a healthcare facility, and the proliferation of legionella is potentially the most dangerous. This bacterium colonises in stagnant water between 20 and 45°C, which can occur in poorly designed, installed or maintained pipework. As the average human body’s core sits between 36.5 and 37.5°C and the environment within people’s lungs is moist, patients and staff inherently provide an ideal space for bacterial growth. This highlights how crucial it is to prevent the spread of unwanted microbes.

To avoid stagnation, every inch of a building’s pipework needs to be in regular use. Therefore, none of the systems must be isolated from the water flow when existing pipes are rerouted or repaired. Pipework separated from the main flow can either be a ‘dead-leg’ or a ‘blind-end’ and will become redundant, creating a situation where water can lie stagnant and become a prime reservoir for bacterial growth.

Even if the system is designed correctly and maintained, so that there are no ‘dead-legs’ or ‘blind-ends’, after some time, traditional pipe materials such as copper can be compromised by limescale build-up, which can harbour bio-film and bacterial growth. The contamination can begin even before the pipes are installed, as often the pipe ends are unprotected before installation, allowing dirt and bacteria to enter the system. Once the bacteria have established into a bio-film within the pipe, then these contaminants become very difficult to remove.

Reducing the risk of bacterial contamination

It might be a cliche, but, indeed, prevention is always better than cure. To effectively prevent legionnaires’ disease from getting a foothold within a healthcare facility, the building’s owners and managers need to make sure that the water system can minimise the chance that bacteria will be able to grow and thrive within the pipe network.

A water management programme team should be established which understands the building’s water systems and usage, can identify problem areas, decide on control and monitoring measures and know how to take action when required. The team should recognise that each water system needs to be tailored to the building in question. Variables to consider include the facility’s structure, size and age, its location and surroundings – if there are unique areas of risk for legionella growth – and how susceptible the occupants will be to a legionella outbreak.

Advances in water network design mean that solutions are available, which cut down on the possibility of stagnant water and the potential for bacterial growth. Multi-layer composite (MLC) pipes made from a core of aluminium and layered inside and out with polyethylene have an extremely smooth inner surface that significantly reduces the chance of limescale build-up.

MLC pipes supplied in a coil are also highly flexible and can be easily formed to suit the building or to navigate around obstacles, meaning that a joint-free pipe system can be created between the water source and the outlet. In contrast, traditional 3m-long stainless-steel and copper pipes require a lot of connections due to their rigidity and fixed length. These connections can have small crevices where bacteria can accumulate, so avoiding the need for connections makes the water system safer.

MLC pipes can be combined with installation techniques that will further enhance hygiene levels. This includes using a ‘loop’-style configuration which sends water through the whole local network each time a water outlet is turned on, stopping water lying stagnant or lengths of pipework becoming redundant. Compared to traditional ‘T’- or branch-type installations, loop designs use a singular, consistent pipe size and require fewer connections.

Designing for long-term hygiene

The potential threat posed by bacterial contamination of the water supply in a healthcare setting is undoubtedly severe, as it would unavoidably put many patients in a difficult position. Anyone within that facility with a compromised immune system or who is of advanced age or suffering from a chronic medical condition would be at particular risk. To add to the challenges that this scenario would cause, it would also be challenging actually to pinpoint where the problem would be coming from. This difficulty stems from the fact that infectious illnesses in the immunocompromised are often hard to diagnose and the cause of the outbreak may be attributed to chance contamination before the on-site water system is correctly identified as the source.

This issue further highlights why it’s crucial to make sure that the water network is appropriately designed in the first place and that its installation, maintenance and ongoing use are all taken into account so that the potential risk of contamination is as low as it possibly can be.

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