Disinfection of biosafety cabinet surface microenvironment by hydrogen peroxide dry-mist

Disinfection of microenvironment surface is very important for control contamination of biosafety laboratory.Hydrogen peroxide has been used widely in biosafety laboratories for disinfection.The effect of hydrogen peroxide on inactivation of different bacteria was investigated in the present study.The effect of hydrogen peroxide in the form of dry-mist(diameter10μm)on sterilization of common pathogens in the biosafety cabinet(BSC)was evaluated.The optimized procedure(diffusing 1min for 8cycles,reaching 60 ppm,and staying 2h)has been determined,at which hydrogen peroxide dry-mist was able to completely kill 6logs of Staphylococcus aureus(S.aureus),Staphylococcus epidermidis(S.epidermidis),Mycobacterium smegmatis(M.smegmatis),Bacillus subtilis(B.subtilis)and Bacillus stearothermophilus(B.stearother-mophilus),as well as 8logs of Escherichia coli(E.coli),but not 7logs of S.aureus,S.epidermidis and M.smegmatis.Therefore,it is suggested that before disinfection of BSC surface microenvironment by hydrogen peroxide dry-mist it is necessary to wipe the BSC surface or decontaminate spillages with disinfect-ants.