A non-sterile substance (e.g., a solution, spray, cream, gel, or powder) intended to be applied by a patient in or around the nasal passages to create a barrier for airborne contaminants/irritants (e.g., allergens, bacteria, viruses) to protect the nasal passages from exposure and/or to minimize their inhalation. It is normally available [non-prescription] over-the-counter (OTC). After application, this device cannot be reused.