Samples are taken on site by certified employees of the health authority or accredited laboratories. As a rule, the public health department provides you with a list of accredited laboratories.
The sterile samples are then incubated in the laboratory. The first result is available after about seven days. The more precise determination of the legionella strain takes about two weeks.
Preliminary information can also be provided by various rapid legionella tests, with which genetic material of legionella can be detected. However, these tests cannot be used legally. In addition, they can also be used to detect dead legionella, which can be present, for example, in the course of thermal treatment. We therefore recommend that you contact a qualified body if you suspect a legionella infestation.
In addition, a contamination is notifiable. And be careful: Knowing about a Legionella infestation without remedial action is considered a criminal offence.