Vial adaptor, hermetic

Vial adaptors are sterile devices fitted to vials to allow airtight removal of vial contents into a syringe, typically comprising a housing that attaches to or replaces the vial lid and incorporates a sealed expansion chamber for closed pressure equalisation to prevent the egress and ingress of materials such as vapours and microbes. These devices are intended to access drug vials of various sizes whilst mechanically prohibiting the transfer of environmental contaminants into the system and the escape of drug or vapour concentrations outside the system, thereby minimising individual and environmental exposure to drug vapour, aerosols and spills.