on a related note, and not to burst anyones bubble specially in NOVA. my last emissions class the epa instructor suggested that va state police and epa are currently studying a program where coal rollers will be cited for polluting.
diesel sooth is considered particulates and in the commonwealth "it is unlawful to knowingly release harmful particulates into atmosphere".
va and epa are looking at a similar program in NJ, where if you are caught rolling coal you are scorted to a testing station where you are submitted to diesel emissions test, if you fail or decline diesel emissions test
and you are out of state you are cited and scorted out of state and not allowed back until you show proof of being a non gross polluter, if you are a commercial vehicle your authority can be suspended "dot number", if you're a private vehicle and are caught a second time you may face jail time. (yes "they the law" call them "coal rollers" gross polluters)
if you are nj state resident, your registration is suspended until you pass test as well as cited. All of this according to epa data obtained or offered thru Va emissions class.
no word on if or when and they plan to implement this regulation here in NOVA.