"It gets very dry here in the midwest during the winter. This is NOT urban
legend"

Here we go again. I too, live in the mid-west and have had an ungrounded
plastic piped system about 20 years, no sign of static problem. We are
talking home shop here, not commercial shop. A post a couple of year ago,
using Gov. figures, estimated that you would have to reduce a 6" pc of Oak
4x4 to dust in about one minute to get a great enough concentration to
cause an explosion.

Walt Conner