The final study presents an examination of tap/potable water samples to which targeted concentrations of the bacterial strain Legionella bozemanii (ATCC 33217 Fluoribacter bozemanae) were added. Sampling was performed according to BS 7592; 2008 (Section 2; Routine sampling) and the water analysis was performed acording to norm HRN EN ISO/ IEC 11731: 2017. Each sample was processed on two types of selective nutrient media (BCYE and GVPC) andprocessed with 14 different procedures. After 4 days of incubation at 36 °𝐶 (with 3% CO 2 ), the first reading / examination of the specimens was performed. Legionella bozemanii, like certain other strains, exhibit auto-fluorescence when viewed with the ultraviolet light. It is the characteristic of the tested bacterium that enabled us to detect it with the help of a hand-held fluorescent lamp on prepared nutirent media. After detection of fluorescent strains, additional confirmation was made by inoculation on BCYE nutrient media (with or witohout the addition of the cysteine amino acid). The final results after 10 days of incubation period clearly showed that the abundance (CFU) of legionella on nutrient media was consistent with the added concentrations of L. bozemanii.