Patent ID: 7152600

Claim:
A biohazard mask comprising: a curvilinear surface forming a face volume and having a substantially annular edge, the annular edge forming a face seal; at least one inhalation aperture within the curvilinear surface; an inhalation filter disposed between the inhalation aperture and the face volume; an inhalation valve disposed to allow air to enter the face volume through the inhalation aperture and the inhalation filter, but not to allow air to escape in the other direction; at least one exhalation aperture within the curvilinear surface; an exhalation filter disposed between the exhalation aperture and the face volume, said exhalation filter contained within a cartridge which is removable and replaceable; and an exhalation valve disposed to allow air to exit the open volume through the exhalation aperture and the exhalation filter, but not to allow air to escape in the other direction; whereby, the biohazard mask filters both inhalate and exhalate.