38th Floor. If there is a fire, my office will be above it or at the same level. Based on the results of 9/11, I'd prefer not to be on the top floor. Oh well.

I've been reviewing the Xcaper product line. It looks to be a significant improvement over the N95 that is currently in my kit. I notice that Xcaper has a "high altitude" filter and a professional filter, and that the high altitude filter is very inexpensive (approx. $7.00). The company's website has testing results from an indepenent laboratory. I assume the tests were conducted on the professional filter. It would be interesting to see if tests have been conducted on the high altitude filter and if so how it performs in comparison to the professional filter.