Domestic water


Detection through analysis

Implementation of best practices known to control the growth of Legionella drastically reduces the risk of infection, but the emergence of the bacterium can still occur in a treated system. Impairment of the procedure, a drift of the process' conditions or any other incident which may boost the development of microorganism may leave a fertile ground for the proliferation and possible infection of exposed persons. The screening by specific analysis of Legionella is the ultimate barrier to detect its presence in water and adjust the preventive maintenance without delay.

The detection of legionella bacteria must be carried out in a laboratory using standardized and specific methods. Depending on the circumstances, a method by measuring DNA or development on culture will be preferred.

The method by measuring DNA analysis allows to detect and measure the population of legionella in water or in biofilm by analyzing their DNA. This method gives a result within 24 to 48 hours. It is therefore an extremely powerful tool for detection and its rapid response facilitates the application of disinfection processes and limits the exposure during an outbreak.

The culture method is based on the development of bacteria on agar plates with several different types of treatment. It is grown on culture media and can be counted efficiently after an incubation period of about 14 days. The culture method identifies more precisely the viability and virulence of the bacteria, and important clinical information in some cases.

Methods of disinfection

Disinfection of a domestic hot-water system contaminated with Legionella bacteria requires the use of proven technologies that are acceptable in a potable-water context. Although in most situations the required response is one of treatment, it may also be necessary to set up a preventive maintenance program to control the bacteria’s growth. Magnus offers treatment technologies that are adapted for these systems.

  • Chlorination;
  • Chloramination;
  • Catalyzed peroxide;
  • Chlorine dioxide;
  • Copper/silver ionization;
  • Thermal disinfection.

Depending on the chosen technology, temporary or permanent installation of equipment may be required. The choice of treatment should take into account the mechanical constraints of the system to be treated: the treatment is applied according to the restrictions on use particular to the disinfectant chosen. In all circumstances, the objective is to effectively control the Legionella bacteria while maintaining the quality and wholesomeness of domestic water.

Consult our domestic water action plan