Aim. Assessment of operational block employees’ knowledge about threats related to improper air quality in the operating room. Material and methods. The study was conducted among 70 employees of operating blocks at two Warsaw hospitals. The evaluation used the survey method. The survey contained 30 questions. Results. Medical staff presents the smallest knowledge in the field of pathogen expansion (n = 21, 30%), knowledge of medical waste codes containing microorganisms and their toxins (n ​​= 17, 24%). The respondents gave the most correct answers about the dangers caused by conversations during surgery (n = 49, 70%) and the presence of additional people in the operating room (n = 60, 86%). Research shows that awareness of medical staff about the importance of air quality in the operating room is insufficient. Conclusions. 1. The examined medical staff had knowledge mainly about practical aspects related to work in the operating room. 2. Medical staff of operating theaters mostly declare their willingness to participate in trainings on air purity and quality, which could significantly increase the amount of knowledge on this subject.

Key words: operating room, air conditioning, air quality.