I brought a hand held dust monitor into the MC tube when I was taking beam spot photos in support of baffling in HAM3. With gentle steps (soft impact between chamber floor and boot) and fully counting 1001, 1002, I could keep the level well under 100 particles >0.5um per cubic foot. Speeding up increases the level dramatically. I found a few large particles under the HAM2 ISI, but I did not wipe under there for fear of suspending smaller particles. I think that the best thing we can do for dust is to learn to move slowly when we are in chamber.