Background: Microbiological surveillance is an important part of infection control program, providing data regarding types, and counts of microbial flora. Aims:This study was carried out with the aim of isolating and identifying the character of microbial contamination in tertiary care hospital by air, surface and equipment OT. Materials and methods: Six months of retrospective study was performed of by random data collection of the hospital's six OT's. Air sampling was performed using settle plate method. Surface samples were taken from various OT sites and equipment. This isolated and described bacterial species using traditional methods. Results: A total of 95 air samples were collected for 2 year from 5 OT’s, 3 ICU’s and 1 LR. The bacterial CFU/m3 counts of air from all OTs ranged from, Labour room showed 75 CFU/m3 , general surgery 69 CFU/m3 followed by PICU and NICU 63 CFU/m3 . least is ophthalmology OT with 6 CFU/m3. Out of Total Positive Bacterial isolates most commonwas Bacillus (54.7%), followed by CoNS (22.1%) andleast common Staphylococcus aureus (1.1%). These 95 culture positive isolates. Bacillus spp. with 52 (54.7%) isolates was the most common bacterial isolate followed by coagulase-negative Staphylococcus (CoNS) with 21 (22.1%) isolates. Conclusions:The study revealed that our hospital's OT's showed a low on surface swabbing rate of bacterial contamination and that CFU counts per mm3 of air quality were within permissible limits.

Keywords: Microbial contamination; Hospital-associated infections; Coagulase-negative Staphylococcus