AEROSOL AND EVAPORATION METHODS FOR THE D ISINFECTION OF SMALL FARM-BUILDINGS

The efficiencies of an aerosol and an evaporation method, in combinati on with new disinfectants, for the disinfection of animal houses were investigated. Formaldehyde formic acid and a disinfectant based on eth er oils were used Ent. faecium, S. senftenberg and ECBO-virus LCR-C we re used as the test microorganisms. Initially, the efficiency of the d isinfectants was examined in dilution tests for their bacteriostatic e ffect and in suspension tests for their bacteriocidal and virocidal ef fects. In the practical tests two aerosol generators were used: Master drop MD 2500 (particle size d(50) 3.8 mu m). Two steam pots were used for the evaporation methods. The studies were conducted in an animal h ouse of 44.96 m(3). Ent. faecium and S. senftenberg were used at two c oncentrations (10(3)-10(4) and 10(7)-10(8) cfu per carrier which was l imewood/aluminium). The disinfection of ECBO-virus LCR-4 was tested at one concentration of 10(7) CID50 per carrier (poplar wood). The resul ts indicated that disinfection by both methods is effective for small buildings. The recommended concentrations of disinfectant were 5 g/m(3 ) or 8-12 g/m(3) formaldehyde, dependent on the cleaning level achieve d with an exposure time of 2 hours. In buildings without corrosive equ ipment formic acid can be used in place of formaldehyde at a concentra tion between 40 g/m(3) and 60 g/m(3). The use of disinfection using et her oils is not recommended.