Elliott Linnane, Water Risk Supervisor at 4site Consulting answers commonly asked questions about Legionella.
Elliott Linnane is a Water Risk Advisor at 4site Consulting and has spent over half a decade working as a renowned qualified advisor within the industry. Through 4site, Elliott provides Legionella Risk Assessments, Schematics and Monitoring, and Legionella Management Log Books, as well as bespoke advice to a large portfolio of property management clients across the country.
Below, Elliott has answered some commonly asked questions about Legionella and Legionnaire’s Disease.
What is Legionella?
Legionella is a wide spread naturally occurring bacteria that can cause a number of illnesses (grouped as Legionellosis).
There are over 40 different species of legionella bacteria. However, legionella pneumophila is considered the most dangerous as it causes about 90% of the cases of infection.
Legionella is considered a biological hazard and is listed under the COSHH Regulations. This defines the need for a suitable risk assessment to cover water systems in the work place.
Legionella bacteria can grow in purpose-built systems, such as hot and cold water systems, if the conditions are favourable (i.e. if temperatures are between 20-45 °C, water is stored, or has organic matter in it).
Have you personally had any encounters with Legionella?
Yes. In the early years of my career, I was instructed to attend a Primary School in Essex to complete a routine 6 monthly monitoring inspection. A 6 monthly/by annual check for this particular client involved:
- Sampling the Cold-Water Storage Tank
- Shower Clean and Descaled
- Temperature checks
During my initial inspection of the school, nothing in particular stood out as concerning. Temperatures for the outlets fluctuated through the site (but were within Acop L8 guide lines), calorifiers flow and return was fine, and the tanks were clean. However, because it was the summer, the temperature of the Cold Water Storage Tank was a little high. It has become obvious that this had led to growth of bacteria and the lab results for the tank came back as positive for Legionella.
Thankfully, no one was infected with the disease as it was caught quickly, and the tanks were cleaned, monitored and sampled monthly to prevent another outbreak. This experience really shows the importance of not only a Legionella Risk Assessments, but regular water monitoring as a control scheme.
How is Legionnaire’s Disease Contracted?
Legionnaire’s Disease is most commonly contracted through the inhalation of aerosols that are contaminated with legionella bacteria. The most common example of this is contracting the disease from a shower system.
Personable factors, such as smoking, can make individuals more susceptible to developing the disease. Other characteristics include:
- Heavy drinkers of alcohol
- People suffering from chronic respiratory or kidney disease
- Anyone with an impaired immune system
- People over 45 years of age
- Men (interestingly, the illness occurs more frequently in men than women at a ratio of around 3:1.)
What are the Symptoms of Legionnaires Disease?
The symptoms of Legionnaires disease are actually very similar to that of a severe flu. Unfortunately, this means that it often goes undetected. Some of the systems include:
- High temperature, feverishness and chills
- Cough
- Sputum
- Muscle pains
- Headache
- Pneumonia
- Diarrhoea
- Signs of mental confusion
How do I prevent or control the risk?
To answer this question, you should consider whether you can prevent the risk of legionella in the first place (by considering the type of water system you need). For example, you may want to consider whether it is possible to replace a wet cooling tower with a dry air-cooled system or remove stored water.
The key point is to design, maintain and operate your water services under conditions that prevent (or control) the growth of legionella bacteria. Some of the ways in which you can do this include: ensuring that the release of water spray is properly controlled, avoiding water temperatures and conditions that favour the growth of legionella, and ensuring water doesn’t stagnate anywhere in the system.
It is also possible to treat water to either kill legionella (and other microorganisms) or limit their ability to grow.
Do I need to have a Water Hygiene Risk Assessment carried out?
In short, yes. Assuming you are an employer or person in control of a premises (e.g. a landlord), you have health and safety duties to take suitable precautions to prevent or control the risk of exposure to legionella.
Therefore, carrying out a legionella risk assessment falls under this responsibility! Risk assessments will help you to establish any potential risks and implement measures to either eliminate or control them. A Water Hygiene Risk Assessment can be carried out by someone from within your own organisation if they are competent to do so. If not, it should be carried out by someone with the necessary skills; such as an external consultant/ advisor.
