Abstract: There is provided a respiratory protection device comprising a mask body defining a breathable air zone for a wearer and having a front cover; an exhale valve in fluid communication with the breathable air zone; and a seal check mechanism disposed in the front cover, where the seal check mechanism comprises a button associated with a flap such that, when actuated, the flap biases the exhale valve in a closed position. There is provided in some embodiments a plane of the button intersecting with a plane of the exhale valve. There is also provided in some embodiments the button and the plunger being a monolithic part.