∗If procedure likely to cause droplet contact, use medium risk procedure.
∗∗If procedure likely to generate aerosols, use high risk procedure. ∗∗∗ECDC (European Centre for Disease Prevention and Control) recommends the use of FFP3 masks for performing aerosol-generating procedures [15]. In case of shortage of Class 3 respirators, the use of Class 2 respirators (e.g. FFP2) may be considered, on a case by case basis and after assessing the risks of the procedures required.