Scanning Electron Micrographs (200x magnifications) showing dust distribution in the top, middle and bottom layers of a new residential carpet. The images show the carpet layers before and after contamination with ATD (Allergen Test Dust), followed by cleaning consisting of vacuuming and hot water extraction.
| Top | Middle | Bottom | |
| Before Dust Contamination |  |
 |
 |
| After ATD Introduction |  |
 |
 |
| After Cleaning |  |
 |
 |