Legionella prevention

If you answered yes to either of these questions, then you must comply with the HSE’s revised code of practice for the control of legionella in water systems, ACOP L8.
Legionella is a name give to a group of bacteria which can, given the right conditions for growth, cause a potentially fatal form of pneumonia which affects the lower respiratory tract. The bacteria remains at a dormant state below 20°C. However, if cold water cisterns and pipework temperature is allowed to rise above this the bacteria proliferates at an alarming rate. The optimum temperature for the bacteria to grow is 37°C (core body temperature) which is why legionella bacteria can take such an effect on the body. There were over 450 reported cases of legionella recorded last year with fines in excess of £300,000.Don’t be caught out, as a manager you are responsible.


The requirement to undertake risk assessments for all water systems and implement a proper control regime was included in the first HSC Approved Code of Practice dating from the early 1990’s. However there are still sites that have chosen to ignore, or are not aware of, the requirements and this can lead to a risk to public health and possible prosecution.

Hydraguard offer a full range of services, from ACOP L8 Risk Assessments, including schematic diagrams, asset lists and prioritised lists of remedial works, to completion of all the required works and ongoing maintenance.

By following the basic steps towards effective control the problem of legionella can be prevented. At Hydraguard we have over 25 years experience of bringing water systems into line with the required standards, and providing the maintenance, record keeping and analysis required by ACOP L8.


We drain, clean and disinfect existing systems where required, and also provide mains injection disinfections of new pipework as laid down in ACOP L8, and BS6700 standards for new systems. Online disinfection can also be carried out if required.

After the work will then provide full validation of results with water analysis.


It should first be stressed that many people who inhale water droplets or water vapour that contain Legionella bacteria either do not become infected at or suffer no serious symptoms if they do. However, for those that do become severely infected (and, incidentally, those who are responsible for the source that causes the infection) the effect can be disastrous.

The immediate impact of a Legionella attack is on the pulmonary system, with the victim experiencing one or more of the following symptoms:

  • Breathing difficulties
  • Coughing
  • Headache
  • Fever
  • Muscle Pains

In most people, as with the majority of bacterial infections, a course of antibiotics will clear the problem relatively easily. However, for those who have a compromised immune system, those who are heavy smokers, those with pre-existing pulmonary conditions and the elderly and otherwise infirm, the infection can be serious, if not deadly. Within these groups, death from Legionella infection can be as high as one in three. The usual cause of eventual fatality is pneumonia, as it is the lungs against which the bacteria primarily launch their attack.

How to Minimise the Risk of Legionella Infection

Because it is now widely recognised that the majority of potential Legionella infections are from collections of warm water, various procedures have now been developed to reduce the risk that emanates from these sources. These measures include regular inspection and, where necessary, positive measures. Contact us on 01751 475964 or info@hydraguard.co.uk

Frequent testing of water temperatures can help to ensure that they do not reach levels where the bacteria become active. If the temperature monitoring reveals that there is a risk that dangerous temperatures have been reached, treatments, which may include flushing out and/or disinfection of the water system involved, can ensure that, where the bacteria have become active, they are killed off quickly and effectively.
Recognition of potential sources of Legionella is essential to the effective monitoring of the safety of water sources and the rapid prevention of any potential Legionella outbreak arising from them.


Although the risk of contracting a Legionella infection may seem unlikely, there are, in fact, several hundred reported cases every year. One implication of this number of infections is that many have contracted the infection whilst in some form of residential establishment, resulting in potential legal liability for the owner of the establishment.
When this type of infection may also result in death, the importance of introducing a relatively inexpensive system of regular water treatment and monitoring becomes all too obvious.