An N95 mask is not oil resistant. It filters 95 % of airborne partials and is good for cutting concrete, painting and sanding, landscaping. Often uses a carbon filter (PM 2.5) It will protect the wearer from the environment. It is 90% effective against Covid-19
An N100 mask is not oil resistant. filter 99.97% of particles It is good for COVID 19
Surgical face mask
A surgical face mask has ear loops and creates a physical barrier between the mouth and nose and contaminants in the environment. protects the environment from the wearer. Is 60-80 % effective against Covid-19
There are no studies on homemade masks
What is important about a mask?
Fit testing is important. Face mask seal is important and facial hair is not a good idea as it can leave a gap. OSHA requires fit testing for employees that regularly must make use of a mask at work as part of their job
Remember that the right mask worn the wrong way will not protect you. It is just as important to do fit testing for the proper sizing of masks. Make sure employees know how to properly put on and adjust masks to ensure a good face mask seal. OSHA requires annual fit testing for employees whose job description requires the regular use of a mask.
Facial hair does not allow for a good face mask seal and can leave a gap for particulates to enter the airway.
During shortages of premade masks, you could also make your own homemade particulate-filter mask from tightly woven cotton fabric. Instructions on how to do this can be found on the CDC website.
One of the main uses of a mask is to stop people from touching their face