Double masking:
✅Cloth over medical
-the filtration of the medical mask material plus the edge seal of a good-fitting cloth mask is a great combination
❌Anything over N95
-interferes with fit
-do this only if because of resource constraints, you have to wear your mask repeatedly or for long periods, and you also need to shield your N95 from external splashes. Recognize that with a mask over it, even if you were fit tested for that mask, you might not pass a fit test. However, still much better than a medical mask alone. Just not as good as an N95 alone.
More and references:
https://maskevidence.org/double-masking