Science Questions with Surprising Answers
Answers provided by
Dr. Christopher S. Baird

How does dust get in a house when the doors and windows are always closed?

Category: Health      Published: April 29, 2013

dust
Public Domain Image, source: Christopher S. Baird.

Dust is more than just bits of dirt and sand from outside. In fact, any solid matter that is broken into small enough bits to be blown around becomes dust. Outside, common sources of dust are dirt, sand, pollen, and pollution. Indoors, common sources of dust include dead skin and hair cells from humans, the carcasses and waste products of microscopic creatures such as dust mites, as well as worn down bits of clothing and furniture. Dust is unavoidable because all solids slowly wear down. However, indoor dust can be minimized through a variety of techniques:

Topics: dust, dust allergy, dust mite, filter, house dust, indoors