WASH YOUR HANDS, MAINTAIN A DISTANCE, GET SOME EXERCISE & SUNSHINE

The PM 2.5 Activated Carbon filters are a very effective filter.
(The PM 2.5 filters can be used for 48 - 72 hours on average, depending on the level of pollution)
Coffee filters are being used as an inexpensive (but not as effective) alternative.
It's up to you to decide the filtration level you require.
Here is an article on the filtration abilities of some materials.

      


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