The control of the air quality in the surgical area is recognized as being critical and this control is significantly affected by the type of air ventilation system adopted. Measurement and prediction of particle concentration, dispersion and distribution in an operating room is very important for a good understanding of particle transport and for the development of control measures, creating and maintaining a healthy indoor environment. This study investigated the movement, distribution and concentration of particles in an operating room ventilated with split systems using experimental measuring and computational fluid dynamics techniques (CFD). Different simulations were realized and the numerical results were compared with experimental results. The measurements were accomplished at a Brazilian hospital representing a real surgery procedure. The result showed that there is a potential infection risk because of the random particle distribution inside of room and the intense deposition of them on the surface in general. Then, based on the results, this study suggests that the split systems are not appropriate to be used in operating rooms and represents a risk to patients and healthcare professionals in this room.