@ Fredog .. years ago when PrePass first came out.. I had a pamplet with listed which ones were Ok to bypass with placards.. but can't find it now..
Looking for an online resource now, but so far just the PrePass site gives this information:
Like Arkansas: not permitted to bypass with oversize/overweight ( even with a permit), and placarded hazmat or haz waste.
Arkansas
Alabama restricts: Livestock, Bulk Fuel, Agri & oversize/overweight(even with a permit)
http://www.prepass.com/services/prep...onAlabama.aspx
What you Know... they've have gotten it down to only 2 states: Arizona & Arkansas where you can't bypass(prepass) with hazmat. Plus, Ohio & West Virginia requires you to have their State issued Hazmat permit-- you can't PrePass unless you have their permit in your Permit book.
Of course, last time I checked-- bulk fuel usually required Placards so can you include a couple "special" cases there.