Just so that tid bit of information about dropping humidity with ris doesn't actually get used .....
Keeping the humidity low will only dry the lungs out causing scarring which will cause EVEN MORE issues. You never want to drop humidity with an Ri. Ever. Low humidity is also a cause of Ris.
Keep humidity up. That allows the mucus to come up and out and not sit in the lungs.
Think of it like when you have a really bad cold or bronchitis a hot steamy shower always helps clean that crap out.
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