hazeljane, the mental picture of you banging them on the railing made me laugh. Yes, I have a Hepa filter on my vacuum. I have a really good furnace filter that we change frequently too. :) If I end up washing these, I will ask hubby to vacuum off the sides, so I get rid of most of the dust beforehand. I just wonder if they will continue to produce dust after I wash them, due to those pinked edges. Now that's something I hadn't thought of.