Drinking Water


Legionella monitoring of hot water systems by sample collection and laboratory analysis.

The Drinking Water Directive obliges all operators of commercial drinking water systems with a storage capacity of more than 400 litres to carry out periodic tests for Legionella. Exceeding the technical measure value (100 CFU in 100 ml) indicates technical defects in the system that allow Legionella to multiply.

Legionella are naturally occurring bacteria that multiply strongly at temperatures of 25 to 45°C. They are transmitted by inhalation via fine water droplets (aerosols), such as those produced when showering. Hazard risks are found in

  • Private houses/flats
  • Hotels/accommodation establishments
  • Kindergartens/schools
  • Fitness/sports centres
  • Hospitals
  • Swimming pools/saunas

Legionella can cause illnesses with flu-like symptoms or severe pneumonia, which in the worst case can be fatal. They only die off at temperatures above 55°C. The temperature in the hot water tank of a drinking water system must therefore be at 60°C to ensure that the temperature in the entire distribution system does not drop below 55°C. If this is the case, there are technical problems. If this is nevertheless the case, there are technical defects.

4base lab is an accredited testing laboratory (certificate) according to DIN EN ISO 17025 and a water testing body listed by the Ministry for Rural Areas and Consumer Protection.

Parameters of microbial water analysis

  • Escherichia coli
  • Coliforms
  • Colony count@ 22°C
  • Colony count@ 36°C
  • Enterococci
  • Pseudomonas aeruginosa
  • Legionella spp.

Sampling is carried out by our certified personnel.

Further on-site parameters:

  • Temperature
  • pH value
  • Conductivity

Examination of dental units: 

Biofilms can form in water-pipes, which enable or promote the propagation of germs such as Legionella or Pseudomonas species. Regular water checks are crucial as part of a required hygiene plan for quality assurance and prevention of infection.  You may choose from the following packages:

  • Examination package 1: Legionella, Colony count @ 36°C
  • Examination package 2: Legionella, Colony count @ 36°C, Pseudomonas aeruginosa