Patent ID: 6460539
Filing Date: 2002-10-08
Classification: A41D,A62B

Abstract:
A negative pressure respirator that comprises:(a) a mask body that defines an interior gas space and an exterior gas space, the mask body comprising an integrally-disposed inhale filter layer for filtering inhaled air that passes through the mask body; (b) an exhalation valve disposed on the mask body, the exhalation valve having a valve diaphragm and at least one orifice, the valve diaphragm and the orifice being constructed and arranged to allow an exhale flow stream to pass from the interior gas space to the exterior gas space; and (c) an impactor element that is disposed on the exhalation valve in the exhale flow stream; wherein the exhalation valve and impactor element provide the respirator with a ratio of Zn/Dj of less than about 5.