<prompt> Operation theatres are sterilized by?Carbolic acid sprayingWashing with soap and waterFormaldehydeETO gas  <response>: FORMALDEHYDE GAS is used for sterilizing instruments and heat sensitive catheters and for fumigating wards, sick rooms, and laboratories REF:Ananthanarayan and Panickers Textbook ofMicrobiology 8thEdition pg no:36 