Data on laboratory study of 367 clinical samples from patients with community-acquired pneumonia diagnosis, 70 samples of cold and hot water from the systems of cold and hot water supply, 15 samples of technical water, 4 samples from open basins, 35 lavage samples from environmental objects, which came to laboratory of control for biological factors in Center of Hygiene and Epidemiology in Sverdlovsk region during outbreak pneumonia caused by Legionella in town Verkhnyaya Pyshma in July-August 2007, were presented. Procedure for laboratory diagnostics was developed, complex of laboratory methods considering the pressure of time in outbreak situation was determined.