evidence: Wearing a respirator or mask is another way to reduce exposures to respiratory hazards. Respirators fit closely to your face and protect you by filtering particles out of the air you breathe. They also filter out droplets and particles that you exhale when breathing, coughing, or sneezing to prevent the spread of germs to others. Masks also filter out your exhaled breath to protect others. If a mask fits closely to your face, it also provides some protection from germs spread by others. [...] Respirators and masks may filter particles and block droplets when you exhale (breathe, talk, cough, etc.). This reduces the risk that a person with a respiratory infection will spread germs to others. If you have a respiratory infection, there’s a change you could pass your infection to others. Wearing a respirator or mask reduces the number of germs that you exhale into the environment around you. This is one way to prevent the spread of respiratory germs from person to person, like wearing a mask to prevent the spread of the germ that causes COVID-19. [...] Respirators and masks intended for particles reduce your exposure by filtering some particles out and blocking droplets when you inhale. They can help protect you from particles like smoke, air pollution, mold, and germs in the air you inhale. They do not filter out harmful gases and vapors such as carbon monoxide or gasoline. It is important to consider the level of filtration and fit when selecting a respirator or mask.