Carpet can act as a filter for dust, pollen etc. Interesting article about this at http://www.carpetinstitute.com.au/good_health/index.htm.

Had to clean a unit today. It involved wiping out cupboards, wardrobes, vacuuming newly layed carpet,cleaning a bathroom and toilet. … More

Go to http://www.flooringtheconsumer.blogspot.com.

The website is http://www.getawhiffofthis.com. I Hope this is also helpful.