Legionella in Nursing Homes

User: Retirement Home in Munich

legionella in waterThe retirement home which called us due to problems with legionella includes three buildings with about 300 apartments. During a routine control of the water a increased concentration of legionella was detected.

The sanitary facilities were put out of order right away. Which is disastrous as hygiene is essential in these nursing homes. In the past these problems were solved through thermal disinfection. This attempt was not successful on the long run.

Thermal desinfection is a costly and time consuming solution which is often not sustainable. Bacteria is killed by using great heat in the pipes. The costs in this case would have been several 10,000€.

The picture shows legionella in a petri dish.

Merus Ring fighting legionella

We started installing Merus Rings at the main water line of the three buildings and the return line to the hot tank. After some successful development seen, we decided to install some more Rings at critical parts of the pipe. As working against legionella is always a sensitive issue, there should be no risk left of contamination.

Before – After

Right after the installation the CFU value decreased about 80%. After some months this number decreased even further until it reached less than 5,000 cfu/l. Only one small part which wasn’t used during this period showed still critical values. Here one more Merus Ring was installed.

After one year this last part (as the others did after six months) reached a level of under 1,000 cfu/l which is the required value by the public health department. Today, 10 years after the installation, the retirement home is still free from legionella.

If you are interested in measurements and monitoring please contact us.


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