—Mandy Gordon, Salt Lake City, Utah House dust comes from dander (bits of skin cells), hair, carpet and rug fluff, clothing and paper fibers, fragments of dead insects, heating and cooling systems and much more. The accumulation has been greater during the pandemic because we’ve been spending so much more time at home. In general, the more activity, the more dust. Before that, we were shedding at the office, at shops and outdoors. Plus, cooking at home fills our wastebaskets with cans, boxes and food waste.