Legionella disease

Legionella in residential home for the elderly; Munich


The Problem

Due to extremely high legionella values the health authority shut down the sanitary equipment in a nursing home, which was built in the 1970s in three phases of construction with a total of almost 300 apartments. After repeated decontaminations by means of heat the legionella contamination increased again very quickly. The costs: several ten thousands of euros.

The solution

At first Merus was only installed at the inlets to the building and behind the hot water tank.

The Result

Shortly after the installation was completed the CFU - values dropped by about 80%. After three more months the numbers dropped further everywhere with the exception of a little used area.
This little used area had only slightly increased numbers in its recorded values. A further ring was placed in this part of the system. About one year later the water in this area also conformed to the compulsory limit value of 1000 CFU/l.
The rest of the system had reached compulsory value after only 6 months. Today, this building is considered to be free of legionella and no longer is on the watch list of the health authority.


Scale in cooling loop Lime scale in a steam boiler Legionella in residential home for the
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