3M 8511 N95 Cool Vent Plug and Cover

thingiverse

I had a box of 3M 8511 N95 masks for working around the house. These masks have an exhaust port on the front for comfort that works well to keep the inside of the mask cool while wearing by allowing exhaled air to exit the mask. Not so good if you are trying to curb a pandemic. My first thought was to print a plug for the inside. The plug can be inserted slightly rotated to get the pins past the crossbar in the mask vent, turned to align the crossbar and then pushed snugly into place. This seems to work fairly well, but doesn't give anyone any indication that the mask exhaust vent has been modified. The second part is simply a cover that fits snugly over the vent from the outside of the mask. Pressure seems to hold it on OK for now. May need to be modified with clips if it becomes loose over time. DISCLAIMER: Neither of these create an airtight seal and there will likely be some bypass exhaust air around either device. They will reduce the amount of unfiltered air exiting the mask. If the 3M 8511 mask is all you have available, these parts may help you to reduce the amount of unfiltered air emitted from the cool flow vent. Be safe and stay healthy.