Abstract The air in dental offices contains airborne microorganisms or bioaerosols. These originate from the patients’ mouths and from biofilms in the dental units and are generated during dental operations. The air/water jet, the turbine and the ultrasonic scaler produce high concentrations of potentially infectious bioaerosols. Therefore, all the air in the room is potentially contaminated by bioaerosols, not just the patient’s immediate environment. Also, this contamination can persist after the end of the intervention. This brochure describes the most effective means for personnel in dental offices to protect themselves from this type of contamination.