Air biomonitoring in working environment before and after ozone treatment

In this work, a technique for indoor decontamination (working room) is proposed by means of ozone application. Due to its characteristics, ozone is considered as a strong oxidant and biocide and permits the inactivation and the destruction of organisms to prevent the spread of airborne diseases. Ozone was produced by a generator at the concentration of 1 ppm and was applied in the working room for 1 hour. Air sampling volumes were taken for psychrophilic and mesophilic bacteria and fungi. The microorganisms are grown in selective substrates and incubated at the right temperature. Fungal colonies were counted and pure cultures were made. Fungi and bacteria counts were expressed as Colonies Forming Units per cubic meter of sampled air (CFU/m3). The same investigation was performed outside the detected indoor. After the ozone treatment, the quantitative and qualitative analyses showed an extreme reduction of indoor airborne fungi and bacteria. The only fungal taxa Aureobasidium pullulans and Penicillium sp. partially outlived the ozone disinfection