“Getting crushed”, just means you are very busy… not sure how you read that, based on your response
As far as the math for the media… It is not twice the thickness, it’s twice the number of passes, since they are discreete filters in series. if layer 1 removes 77% minimum, then there is only 23% left to be filtered by the second… that’s all.
MY intent, when posting was to say thaat during normal respiration… there’s no noticable resistance. However, if you forcibly breathe fast/pant, then you can feel some. I have not worn the mask in an aerobic situation yet, to see if my “fake panting” is true in a more realistic/longer term environment.
I will say that it does appear that an exhaust valve is not necessary. I have a diaphram valve, that was dasigned for a different device that I could, was planning on using on V2, underthe presumption that the water vapor accumulation in the filter would increase the resistance. It appears that there is enough surface area to allow evaporation under basal respiration. So this is actually a benefit to valved masks. In those ony the wearer is protected. Iff the wearer is infected… he is still aspirating all over everyone… in a valved mask. Here, both sides are contained.