The dust most people are allergic to is caused by dust mites. They live on dead skin cells (these come off of us no matter how many times we bathe) and animal danders. I am highly allergic to "house dust" and my doctor tells me to wear a mask if I have to do the dusting. Using a vacuum with a HEPA filter helps. My vacuum is designed for people like me (Dyson is not the maker by the way). Any bagless vacuum causes me problems because you have to empty the dust somehow. :roll: