Do check out the products of Charcoal Cloth (international) Ltd as it has some very great products that cover a who range protection against nuclear/biloogical , or micro particle fall out.
I am just waiting for more info. They do have a company in USA and they can perhaps reply any queries. I am afraid I have no details of this USA branch so do a google search if possible.
Hope this will help some of you looking for a lead on such a product. <img src="images/graemlins/wink.gif" alt="" />