so high, and just like matt talked about, it gets hard to breathe, and it aggravates people's as montasthma, and premature deathn some issues, and it's a serious issue, even if it happens for only a couple of days. >> and we know enough about health issues, lisa, if you're carrying a baby, it can deliver a shock to the feet us that can be severe, so the fact that it's only a few days is not a reason to keep it from ever happening. >> what makes it so bad to begin with? >> the inversions, usually we have snow on the valley floor, and then it's trapped under the lid. and the chemistry changes in those, and it builds up until a storm comes out to clean us out. >> the community is talking about the impact that it's having on local utahans: i have this great video comment from neil. >> i created the twitter box because i wanted to broadcast whether or not i wanted to be outdoors. i'm a cyclist and there's nothing more frustrating to stay indoors because of the air quality. it was picked up by recreational and professional cyclists, as well as a handful of news outlets. >> talk to us about the im