If you’ve purchased a ready-made kit of emergency supplies, you may have a face mask, an N95 respirator, or both on hand. What’s the difference?
Briefly, both are made for one-time use. If you are ill with a disease, such as influenza, that is spread by airborne droplets, both types will help prevent you from spreading the disease. Both will help to protect you from breathing in airborne droplets spread by others. And both will protect the wearer from splashes.
The real difference is that respirators are tightly fitted to protect people from “very small particles” while face masks tie loosely on the face and do not protect the wearer from very small particles.
The Centers For Disease Control lays out the details here, including this important information: very little is known about how masks and respirators will perform during an actual public health emergency such as a flu outbreak. So the recommendation that you have and use masks is based on public health judgment.