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 |  |
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| After ATD Introduction |  |
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| After Cleaning |  |
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