A filtering face mask 10 that has a mask body and a new exhalation valve
14. The mask body is adapted to fit at least over the nose and mouth of a
person to help define an interior gas space when the mask is worn. The
exhalation valve 14 permits fluid communication between the interior gas
space and an exterior gas space. The exhalation valve 14 has a valve seat
20 and a flap 22. The valve seat 20 includes a resilient seal surface 24
and an orifice 30 through which exhaled air may pass to leave the
interior gas space. The flap 22 is mounted to the valve seat 20 such that
the flap 22 makes contact with the resilient seal surface 24 when the
valve is in its closed position and such that the flap 22 can move away
from the seal surface 24 in response to an exhalation to allow exhaled
air to pass through the orifice 30 to ultimately enter the exterior gas
space. A filtering face mask that utilizes an exhalation valve that has a
resilient seal surface can enable the valve to open under substantially
less pressure, which, in turn, may improve wearer comfort.