How do I clean the ifD® Particle Filter?

Rinse the filter with clean tap water. If still dirty, soak it in lukewarm water with a few drops of mild dish soap for 2-3 minutes (not more than 5 minutes), then rinse again. Shake out excess water and place the filter honeycomb-side down on a towel to dry for a few hours or overnight before reinstalling. Never place a wet filter in the air cleaner. (Page 4)