What Temperature Kills Legionella Bacteria in Water?
Legionella Control International
World-leading legionella and water safety experts.
Legionella bacteria are present in many water sources. This includes natural sources, although they do not usually present any issues when in lakes or rivers as they are only there in small quantities.
Most of the time, low concentrations of legionella bacteria do not cause any issues when present in manmade water supplies either. However, there is a significant caveat to that statement. The water supply must be managed, monitored and maintained to ensure the bacteria do not get the opportunity to take a foothold in the system. It is usually straightforward to follow common sense and established safety rules to ensure this does not happen… although if you’re in any doubt the UK’s Health and Safety Executive offer excellent advice and guidance in their ACOP L8 and HSG274 documents.
In this article, we’ll look at the role temperature plays in influencing whether legionella may get the opportunity to colonise a water system, and highlight what temperatures are required to kill legionella bacteria in water systems.
Why is it important to control legionella bacteria?
Legionella bacteria can enter a manmade water system in many ways. Indeed, it is almost impossible to prevent this from happening. However, there are many things we can do to make sure water systems are not at risk of legionella bacteria growing and spreading throughout the system. If this occurs, the risks to safety increase, and people using the water or who are in the vicinity of it may be at risk of developing Legionnaires’ disease.
This disease can be fatal and can occur when someone is exposed to legionella bacteria. It is a potentially serious infection of the lungs, caused when someone inhales the bacteria via water droplets suspended in the air, called an aerosol. Any source of water that generates a spray or mist can therefore be a risk.
Anything from a shower head, spray tap to a water tower or even an ornamental fountain can generate spray, so it is important to conduct a legionella risk assessment to be sure the risk is minimal, and that where risks are identified, you implement appropriate precautions to control them... read more
Senior Consultant Air and Water at RPS
1 年If water is maintained at 50°C for two hours, 90% of the bacteria will be killed off. If water reaches 60°C, the same percentage of bacteria will be killed off in two minutes. If the water reaches 70°C, all the legionella bacteria will die instantly. Although in saying that, there have been instances where legionella had survived even that temperature.
Director
1 年On the other end of the Scale we have Winter and the Risks from Potted Water below 4°C the research from Canada show that Temperature play a big part in the Nora Virus out breaks....It is a Fine Line between getting it right and not getting it right.....
Director
1 年I would feel comfortable at 11°C min Main Delivery and as you suggest above 60°C, there's however different industries that set higher standards and some that set lower Standards inline with Climate Change and Carbon Footprint Shrinkage, which I my humble option leave the public open to exposure. Let hope we do not have any out breaks!
Director
1 年Guide Lines and Industry best practices suggest below 21°C and above 45°C....?
Legionella Consultant
1 年There can be confusion re Legionella and temperatures.Many feel 60°c as the magic temp for killing Legionella.It is killed at this temperature but Not immediately,I believe it is 70°c where it is killed instantly.