Legionella – a challenge for companies

WESSLING is your competent partner for the entire legionella management. We support you in monitoring water quality, with a comprehensive range of analytical services.

Legionellen - Menschen kommen täglich mit Trinkwasser in Kontakt

Every year around 10,000 people in Germany fall ill with Legionnaire's disease, which is caused by Legionella. People come into contact with these bacteria not only via drinking water installations. These rod bacteria can also become a health hazard in process water, wastewater and in the cooling water of evaporative cooling systems.

The experts of WESSLING support operators of water installations and other facilities, and operations according to the Drinking Water Ordinance (TrinkwV) - for the health of tenants, customers and employees.

Infestation with legionella - not only drinking water is affected

Legionella in waterworks can be hazardous to human health

The Drinking Water Ordinance and the EU Drinking Water Directive define that water must be easily digestible and available to humans at all times. To achieve this, operators of systems for continuous water distribution with a large system for DHW heating are obliged to carry out a Legionella test at least every three years.

Legionella pose the greatest health hazard to humans in drinking water. Therefore, large plants are subject to a duty of disclosure. However, care must also be taken in relation to other types of water. Several cases in recent years have shown that circulation water contaminated by Legionella in cooling towers and evaporative cooling systems can be the cause of infections. Some of the diseases can be fatal.

Do you have questions about legionella management?

We will be happy to support you.

Kai Dexheimer
Abbildung einer Verdunstungskühlanlage – auch hier können Legionellen zu einer Gefahr für Menschen werden
Legionellen im Wasser von in Verdunstungskühlanlagen können für Menschen zur Gefahr werden

Trinkwasserverordnung und EG-Trinkwasserrichtlinie definieren, dass Wasser für den Menschen jederzeit bekömmlich und verfügbar sein muss. Um dies zu erreichen, werden Betreiber von Anlagen zur ständigen Wasserverteilung mit einer Großanlage zur Trinkwassererwärmung in die Pflicht genommen, mindestens alle drei Jahre eine Legionellenuntersuchung vorzunehmen. Grundsätzlich gilt der technische Maßnahmenwert von 100 Legionellen pro 100 Milliliter Trinkwasser. Dieser Wert darf nicht überschritten werden.

Im Trinkwasser stellen Legionellen die größte Gesundheitsgefahr für Menschen dar, da sie die Legionellose verursachen können. Daher unterliegen Großanlagen der Anzeigepflicht gegenüber dem zuständigen Gesundheitsamt. Doch auch in anderen Wässern ist Vorsicht geboten. Mehrere Fälle in den vergangenen Jahren haben gezeigt, dass durch Legionellen belastetes Kreislaufwasser in Kühltürmen und Verdunstungskühlanlagen die Ursache für Infektionen sein kann. Die Erkrankungen hatten zum Teil einen tödlichen Ausgang.

The comprehensive range of services of WESSLING

The water specialists at WESSLING keep an eye on all places where legionella can become a danger to humans. Their expertise is based on more than 30 years of experience in water analysis. WESSLING is accredited* for sampling and laboratory analysis.

Furthermore, WESSLING is your partner in all areas of Legionella management. We understand this as process-accompanying consulting combined with continuous sampling and precise laboratory analysis. The aim of our advice is to minimize, as far as possible, the possibility of Legionella infestation.

If a relevant multiplication of Legionella is detected, WESSLING is your competent partner with regard to the remediation measures. As legionella are very adaptable, it is essential to select the right combination of remediation techniques for the respective pipeline system.

Testing laboratory accredited by DAkkS according to DIN EN ISO/IEC 17025:2018. The accreditation only applies to the scope of accreditation listed in the certificate attachment [D-PL-14162-01-00].

Probenahme an einer RLTA-Anlage

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