Solution: Check for legionella

Drinking water hygiene: Checking for legionella bacteria

Drinking water hygiene deals with all questions concerning possible quality impairments of drinking water within drinking water installations. The legal basis is the EU Drinking Water Directive, ÖNORM B5019, ÖNORM B5021, ÖNORM B1300/B1301 and the national Drinking Water Ordinance (TWV).

Biofilms form everywhere where water is in low motion, i.e. also in drinking water systems. Normally, they do not pose a problem and do not impair drinking water quality. Health hazards only arise when conditions prevail that favor germ growth. (Stagnant water and water temperatures between 25 °C and 50 °C).  In practice, this danger arises, for example, when apartments are vacant, in rooms that are used periodically, and in dead pipes. Hygiene problems caused by excessive growth of germs can be reliably avoided by:

• correct planning, execution and commissioning
  operation in accordance with the intended purpose
• avoidance of stagnation
• avoiding unfavorable temperatures between 25 °C and 50 °C.

Legionella, pseudomonads and other bacteria are present in practically all water, even in Austria, in low concentrations. Depending on temperature, nutrient supply and movement in the system, these bacteria can multiply very quickly in technical systems (hot water systems, cooling towers, ventilation systems, …) and become a health hazard. Hygienic planning, proper operation, as well as regular control sampling of drinking water systems, especially for the presence of legionella, help to maintain a hygienically perfect condition of the system.

Carrying out hazard analyses

The aim of the hazard analysis is to identify suitable recommendations for measures to control the Legionella species in order to meet the normative and legal requirements. In doing so, deficiencies in the drinking water system and deviations from the generally accepted rules of technology are to be identified.

Determination of sampling points

In addition to the central sampling points at the drinking water heater, the sampling points of the peripheral risers should ideally be included in the systemic or orienting investigation, so that each riser is recorded and the danger areas can be identified.

Remediation plan

Our experts provide specific remediation measures to restore the drinking water system to a sanitary condition as quickly as possible. The focus here is on hygienic operation in terms of occupational health and safety, road safety obligations, operator duties, protection of uninvolved third parties, etc.

Introduction of plant-specific quality standards

The introduction of plant-specific quality standards including a quality manual and the corresponding training of the employees increase the awareness of the importance of hygienically safe drinking water.