“…The OR is a special unit requiring a clean environment with the fewest number of particles in the air [10]. In addition, during surgical procedures, the team and the surrounding environment release dust particles, textile fibers, and respiratory aerosols loaded with vital microorganisms [11]- [13] that can settle on surgical instruments or enter directly into the surgical site causing surgical site infections [14]. The heating, ventilation, and air conditioning systems significantly influence the operating room environment, including temperature, relative humidity, pressurization, particle counts, filtration, and ventilation rate [3].…”