The water samples may only be analyzed for Legionella according to the Drinking Water Ordinance by accredited and authorized testing laboratories (inspection bodies according to TrinkwV). We collaborate with nationally operating accredited testing laboratories to provide our service throughout the entire country. From our laboratory partners, we can have approximately 90,000 water samples analyzed per year.
Our IT systems are coordinated with each other, so that, for example, the sampling data is made available to the laboratory through a software interface and does not need to be manually recorded or entered later. In return, we receive the examination results (as soon as they are available) as raw data for automated data import via a cloud solution.
On behalf of our client, we have the delivered water samples tested for Legionella contamination (and potentially other microbiological parameters). As a professional sampling company, we have aligned our quality management system with the laboratory partner, taking into account the requirements of DAkkS (German Accreditation Body), in order to ensure a smooth process.
Three aliquots of the water samples are plated onto Petri dishes containing specific nutrient agar medium. 50-80 ml of drinking water are filtered (1 filtration run), and 0.5 ml each is streaked on a plate (2 direct inoculations). These 3 agar plates are then incubated in an incubator at 36°C (+- 2°C) for 10 days. Only after that, the examination result is available. The individual colony-forming units (CFUs) are counted; in the direct plating, the respective results are added up and multiplied by 100 to obtain a result per 100 ml. Please note: Only the more unfavorable test result will be stated in the report!
The entire process from sample collection to the receipt of the validated report usually takes 12 days with us. Unfortunately, it cannot be done any faster. What we can offer is a “status update” after approximately half of the incubation period. Then the plates are examined to see if colonies have formed; if necessary, subcultures are prepared for confirmatory tests.
Important for the client to note: Even in escalated cases, such as an extremely high Legionella contamination (>>=10,000 CFU), the client always receives the test result first. As part of the systemic investigation according to the Drinking Water Ordinance, the contracted laboratory, however, promptly reports any exceedance of the action values to the responsible health authority, along with the note that the operator of the facility has been informed about the test result. The operator of the water supply system is also legally obliged to take prompt measures for health protection.