Reply by DIYaholic

IMO, according to what I’ve read/researched, the only reason to ground a PVC ducted system is to prevent the static build up from discharging and (mildly) shocking you. The “myth” of fire has, supposedly, been debunked. As far as Bags, The top “bag” is a filter, the bottom “bag” is a collection bag for chips & dust. They can’t/aren’t the same. Ceck out the Wynn Enviromental website for more information regarding canister filters.

-- Randy-- I may not be good...but I am slow!