The SNAP device facilitates the safe passage of a nasoendoscope through a surgical mask into the nasal cavity. Aerosolised droplets produced through coughing or sneezing during the procedure will be caught in the surgical mask. One withdrawn of the the endoscope, the one-way valve within the SNAP closes to maintain reduction in potential aerosol spread. It is a single use device which is disposed of once the surgical mask is doffed by the patient.