There are air simulations that demonstrate how surgical masks work. They draw air in from the top and bottom when you take a breath and not through the layer of

There are air simulations that demonstrate how surgical masks work. They draw air in from the top and bottom when you take a breath and not through the layer of cloth. Large air droplets have a harder time physically to go up and down inside the mask, through some emissions do also leak through the same place where air goes in. This basically becomes the leak rate. As a thought experiment, imagine having a crash test dummy head wearing a surgical masks. In the mouth you put CO2 smoke. The smoke is made from fine particular that you can physical feel as being wet and cold. What will happen? The smoke will escape from the bottom and top of the mask, with very little "clean" air coming out through the front. Do the same experiment but have a squirt gun shooting a few small burst of solid liquid. The solid liquid will mostly get stuck in the cloth until it is fully saturated.