Describes the new expectation in Annex 1 for the validation of disinfectants to include the effectiveness of disinfectants on cleanroom surfaces. “Validation studies should demonstrate the suitability & effectiveness of disinfectants in the specific manner in which they are used and on the type of surface material used.” The session covers tests available, choosing high risk surfaces and sharing 10 organisms on 10 different surfaces test data recently acquired for two different disinfectants.