Happy 2012 Everyone! Yea! The 14 foot Non electric hose is fantastic! You can get everywhere with it. Boy let me tell you, I got my Rainbow out yesterday and put the dusting brush on the 14 foot hose & got EVERYWHERE floor to ceiling & I was exhausted when done. I seriously do recommend a Rainbow but let me tell you it's NOT a lazy persons machine! I will say this after owning it for five years. If you get it out, clean EVERYTHING. Cushion, floors, behind tv cords, ceiling fans, under beds. Once you get all this dust out. It really does take quite a while for it to come back, so you don't really have to do a thorough cleaning as often. I've been using mine a lot more here lately. It's funny how when you get it out & use it more, the learning curve is gone & it doesn't seem to be as much of a pain as it once was. I still can't believe the hepa on mine is STILL clean over five yrs later. I even took it OFF the machine to test the airflow to "make sure" it wasn't really clogged up or anything and I noticed NO noticeable increases in airflow with the hepa off or ON.......That to me is pretty darn amazing. An over five year old hepa still working at peak performance. But I've always changed water frequently & cleaned the grooves of the separator religiously. Perhaps that's why. I sometimes think other Rainbow owners may get tired of using it & not do this. You do sort of have to take a little extra effort to maintain it. But I think they will last decades if you do.

I have a similar contact allergy to costume jewelry and you are not going to have any issues from touching nickel. If you had the kind of serious allergy that is triggered by casual touching you would have had episodes in the past since you have probably touched nickel in that manner all your life. Having that kind of allergy, I did some reading on it and it is generally caused from long contact with the skin as well as there being heat and moisture which leeches out the irritant. For most people the real issues are places where one might sweat or there is moisture - e.g. pierced earrings, the back of the neck and it doesn't generally occur were a pendant might touch the skin and so there is less of the kind of movement and moisture where there is less prolonged contact.

Your starting point is hire an air quility engineer to assess the home and existing air handling equipment. For a price the engineer will give you options with their pros and cons. Commercial air conditioning contractor can give you cost estimates from those plans. I would expect the positive pressure solution to be a single make-up air with max cfms of all exhausts combined and controlled by a barometric pressure differential device. Pollen control can be handled with proper hvac filtration. Meanwhile to get as much relief as possible with existing equipment use filters rated at least MERV 10,higher if filter racks will hold thickness. Whatever filter used must fit tight enough to prevent air detouring around them. Remediation plans should include 4" thick filter holders for hvac system which allow using high MERV during pollen season. Very few if any residential hvac contractors are equipped to do what you need. Look for commercial contractor that does clean rooms and such.

Update: It's been about two weeks since I posted and stopped sleeping on those original sheets, and my eye area is completely better. I've been sleeping on my new 100% organic cotton flannel sheets from Garnet Hill for about a week with no irritation (bonus: they're nice and warm!). I also ordered a new 100% cotton fleece blanket from G.H., that's in the wash now and I'll start sleeping with that tonight to see if it causes any problems. It will be interesting to see if I wait maybe 4-6 months and rotate those sheets I suspect are the problem back in. If the irritation returns then bingo there's my definitive answer, it's the sheets. I don't want to chance it right now since I'll be rotating in a new blanket, and the poor skin around my eyes need a break :o(