FAQ: The Lowdown on Legionella

FAQ: The Lowdown on Legionella

By on Jun 7, 2016 in Blog |

Last year marked for us 20 years in Legionella control. We have seen it all, dead squirrels in tanks, pigeons, slugs, we’ve seen shower heads encrusted with so much limescale it looks like its grown a shell. We’ve dealt with all sorts of customers including care homes, landlords, hospitals and we like to think we know everything there is to know about this business. (it’s not bragging if it’s true!!)

We get asked a lot of questions from our customers and people who just want to know a bit more about Legionnaires’ disease and we like to help and inform people, and answer everything they might want to know. We have been asked all sorts, from can I get Legionnaires’ disease from drinking water, to is it safe for me to prance around my garden naked with a water hose (in fairness we have only been asked this once.)

We thought it would be helpful for us to compile a list of our most commonly asked questions and answer them for you! This should help you get your head wrapped around Legionella, and if you do want to prance around your garden naked…how to do it safely.


What is Legionella and Legionnaires’ Disease?

Legionella pneumophila, is the causative organism for most cases of Legionnaires’ disease, which is a type of pneumonia. It was named after an outbreak of severe pneumonia, which affected a meeting of the American Legion in 1976. It is an uncommon but serious disease. Nearly one person dies every day from this, and if the case isn’t fatal, it is always debilitating.


How do people get Legionnaires’ Disease?

People catch Legionnaires’ disease by inhaling small droplets of water suspended in the air, which contain the Legionella bacterium. You can’t get it from drinking infected water, and it cannot be passed from person to person.


Where can you find Legionella?

Legionella is most commonly found in purpose-built water systems where temperatures are warm enough to encourage growth of the bacteria, e.g. in cooling towers, evaporative condensers, spa pools and from water used for domestic purposes in buildings such as offices, hospitals, hotels. It grows best in temperatures from 20°C-40°C.


What are the symptoms of Legionnaires’ Disease?

The symptoms of Legionnaires’ disease are similar to the symptoms of the flu:

    • high temperature, feverishness and chills;
    • cough;
    • muscle pains;
    • headache; and leading on to
    • pneumonia, very occasionally
    • diarrhoea and signs of mental confusion.


Can you treat Legionnaires’ Disease?

In most cases yes. The illness is treated with an antibiotic called erythromycin or a similar antibiotic.


I manage a residential property, do I have any Legal responsibilities to manage Legionella control?

Yes you do. You have responsibility to your tenants, or people living within the property to keep their environment safe, you can watch our video on Legionella Risk Assessments for Landlords here.


Do I need a Legionella Risk Assessment?

A suitable legionella risk assessment is required to cover water systems in any premise (although you don’t need one for your own home). This includes rented housing stock particularly where communal services are present.


How often do I need a Legionella Risk Assessment?

The Approved Code of Practice requires that legionella risk assessments be updated regularly (every two years at least) or when significant changes occur that may render the current risk assessment invalid.


Who can perform a Risk Assessment?

According to the HSE only those who are competent are able to carry out a risk assessment. A competent person should have the knowledge, experience and the necessary skill to be able to manage health and safety. Therefore, this could be yourself, an employee or a specialist like us here at Key Environmental Services.


How should I control Legionella?

Cold Water – If we can manage the cold water temperatures throughout the system to ensure that cold water is stored  and distributed to all outlets within two minutes of opening the tap below 20°C then the cold water circuit will not encourage bacterial growth including legionella growth.

Hot Water – Hot water should be stored at 60°C and distributed and supplied to all outlets above 50°C within 1 minute of operation. This should be above 55°C for health care premises.

Stagnation: Stagnation can be prevented by introducing routine flushing programmes and reducing the volumes of stored water.


What if I get a positive Legionella result from my risk assessment?

If you get a legionella positive result you should not panic! If legionella is identified in your system there are many measures that you can take to eradicate it. Measures such as thermal disinfections, temperature management and chemical disinfections can be used to clean your system. If you obtain a legionella positive result and need assistance or support contact us today.



I hope that this post has been helpful to you and answered any questions you may have about Legionella. However if you do have any more questions don’t hesitate to give me a call on 01789 330830 or email ellie@key-environmental.co.uk


P.S For those of you who did want to run around the garden naked with a water hose, just run the hose water for a minute or two first to remove the stagnated water and you should be fine…oh and make sure the hedge around your garden is high enough to avoid the neighbours…


P.P.S Did you see our blog post on managing the water systems in your home and keeping them safe? You can read that here.