The operating room environment as affected by people and the surgical face mask.

The microbiological counts were determined in an operating room suite of 8 rooms and a hallway. The bacterial counts in an empty operating room jumped statistically from 13 CFU/ft2/hr (+/- 31) to 24.8 (+/- 58.8) when the doors were left open (people in the hallways) and 447.3 (+/- 186.7) when 5 people were introduced. The wearing of a surgical face mask had no effect upon the overall operating room environmental contamination and probably work only to redirect the projectile effect of talking and breathing. People are the major source of environmental contamination in the operating room.