One major weakness of the current N95 masks is that sometimes it doesn't seal very well to the contours of people's faces. When this happens, it doesn't work as well because particles can still travel into the airway via open space gaps.

I personally have not seen this implemented, but one possible solution I believe may work is to apply a thin layer of sticky hydrogen tape right along the edges of the mask so it would act like an adhesive that helps seal the open space gaps as it can fit with the unique shape and contour of each person's face.

Medical hydrogen tape is the same material that we often see being used in those sticky pads that they put on a person's body during an electrocardiogram (EKG) test. It's also the same adhesive that used by those electro pads in TENS pain-relief machines. This sticky adhesive material is safe for human skins and can last multiple uses.

It would be great if someone could add a feature in which you can insert a removable HEPA filter so it can be swapped in and out when needed.