Carbon filters can stop working if the air is very humid. I can't say that's happening, of course.
For emergency odor problems, Ona products are great. The gels and sprays are very effective, the solid products are not quite as good.
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I usually have a can of the spray in the house, but whenever someone who has kids drops by, I end up giving it to them along with some weed, after they tell me they don't smoke because they don't want the kids to smell it. I'm currently spray free, as a work colleague dropped in the other day. He left with a variety of produce and a can of Ona.