Dust Masks
Our first line of defense in most situations is a dust mask. Everyone has seen them they are white paper masks that fit over your mouth and nose and help to stop the larger particles of dust and paint or other larger items from being inhaled.
Their cost and quality can range a bit but because they have no chemical filtration ability you can only use them in situations where a good outside air supply is available and when volatile chemicals and pesticides are not present.
A Volatile Chemical can be seen in Paint Thinners and Gasoline and other products of that type. This is something that you can’t stop without filtration.
Dust masks are generally good for:
Cleaning up job sites
Sawing Wood
Painting Latex or other low Toxic Paints with a spray gun
Light Sanding where no Lead Paint is involved
Use of weed wackers and law mowers in dusty conditions.
Proper use of a dust mask means that the mask will fit tightly on your face. If you have a beard or mustache you are probably out of luck. You can try using one but facial hair is not a known good filter of anything except food getting into your mouth.
Other then that we need to move up to the next level of protection.