Legionella

Legionella is a bacterium that can naturally be found in low concentrations in surface water and soil. Legionella has favourable growth conditions in pipes with stagnant water and temperatures ranging between 20 and 50°C. In such conditions, biofilms form, allowing Legionella bacteria and amoeba to thrive. It is essential to have proper preventive procedures in place, such as weekly flushing of rarely used drain points and measures such as removing any pipe blinds in the internal pipe network to prevent the formation of biofilms. Water heaters must also maintain a high enough temperature (minimum 70 °C) for Legionella bacteria not to thrive.

Transmission of infection

Legionella is transmitted through aerosols, which are small droplets of water that are inhaled into the lungs, for instance when showering.

Pathological scenarios

Legionella bacteria can result in two potential pathological scenarios. One is Legionnaires’ disease, which causes severe pneumonia, with the most vulnerable people being those with weakened immune systems and the elderly. The other is Pontiac fever and resembles a mild form of influenza.

Nemko Norlab

Nemko Norlab conducts laboratory analyses of Legionella. Our laboratory in Kristiansund performs accredited analysis in accordance with the cultivation method NS-EN ISO 11731, while the laboratory in Namdal performs analyses using the PCR method. The PCR method is preferred if you require rapid screening to identify whether there are any Legionella bacteria in the system. Otherwise, we recommend the cultivation method for ordinary sampling, but this method takes longer. Please contact our technical experts (link) for further information.

The guidelines issued by the Norwegian Institute of Public Health recommend analysing for germ count at 36 °C at the same time as Legionella. There is no direct correlation between the two parameters, but the germ count (total number of bacteria and fungi) can be considered a general hygiene parameter and provides an indication of whether biofilm has been established or is under development in the pipe network.

Our members of staff have experience in performing pipe network reviews and can conduct risk assessments together with operating personnel to draw up a sampling plan.

Training

We have extensive experience in providing Legionella training courses. Please get in touch for a quote.

Sample collection

For water sample collection, you will need a sterile 1 L water bottle. This sample packaging is included in our analysis price. You will receive bottles and sampling instructions when you visit or contact one of our laboratories.