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Neighbors are gassing me out of my apartment. What should I do?(r/AskReddit)
“when the door is closed there is an airtight seal all the way around” This. I had basically the same problem of neighbor smoke in my apartment. I used a combination of an airtight door seal, in my case a hippy curtain hung over the door, and an indoor air filter. Doing this basically eliminates the smoke odor, and if the filter is off and I smell smoke I turn the filter up or down accordingly. There are fancier air purifiers on the market that do a better job with smoke, but the honewell has a true HEPA filter and a carbon pre-filter which do a good job with no ozone.
Neighbors who smoke inside suck big time. If you live in an apartment and you smoke inside, your neighbors hate you, please stop, kthxbye.