On Tue, Jul 5, 2016 at 2:44 PM, Van Horn, David < david.vanhorn@backcountryaccess.com> wrote: > Oh. :( > > Last year I was hospitalized 3x for what we thought was a > bacteria/virus/demon in my lungs, but it turned out to be acute irritatio= n > caused by an ultrasonic humidifier putting mineral dust in the air. > > At one point, I was down to 70% O2 after three hours exposure. > > Not sure how to evaluate the risk level Ouch! That's why I use a large evaporative humidifier in the winter and a HEPA air filter all the time. After a couple of weeks, the wick turns into a disgusting yellow-brown colour from all the minerals in the water. But if you have sensitive lungs, I'd strongly suggest you get one of these: https://www.amazon.com/3M-Facepiece-Respirator-6291-Particulate/dp/B000FTED= MM/ref=3Dsr_1_3?ie=3DUTF8&qid=3D1467746622&sr=3D8-3&keywords=3D3m+respirato= r They're cheap, comfortable, and absolutely amazing. I have sensitive lungs and I use those if the air quality around me drops. The difference is immediately noticeable after you put it on. --=20 http://www.piclist.com/techref/piclist PIC/SX FAQ & list archive View/change your membership options at http://mailman.mit.edu/mailman/listinfo/piclist .