As businesses reopen, many employers are looking for ways to protect their employees and their customers. Masks are one strategy. A mask does two things. First, it protects the wearer from breathing in virus someone else is shedding. Second, if we are carrying the virus unknowingly, a mask can protect others.

Virus is often transmitting through the air on tiny droplets of water. Anyone who has ever worn a respirator knows how much water we breath out. How long these droplets stay in the air depends on many variables, including temperature, humidity and other environmental conditions.

When we breath out, these water droplets can be caught by a face covering. Some perform better than others, but not always the ones you expect. To protect ourselves, the ideal situation is a mask designed to block very small particles, such as virus particles. N-95 masks are designed to do this with the material they are made of AND their tight fit around the face. But not all N-95s are created equal.

Some N-95’s have a feature which is designed to increase the comfort of the wearer. Remember all that water we breath out. Well, a one way valve allows a mask wearer to breath out through an unfiltered port in the front of the mask, minimizing moisture buildup and effort to breath out. But also leaving others exposed to virus the wearer may be breathing out.