To over come this it would take a pressurized inclosed trailer with a good amount of pressure and filter system. In the old days when people were allowed to smoke we could find leaks on the aircraft around the rivets and panel seams from the tobacco stains. I don't think you could seal a trailer enough to stop it.
At Bonneville the salt is a major issue and I remember one year when the Rice bros. Put a tarp under thrir trailer (full length) before pulling it on the salt. It made a big difference. I guess a belly pan might work as well but not cheap to do and salt would still get into places that would require dropping that as well to clean the bottom.
Going on El Mirage dry lake I usually drive about 15 to 20 mph and the vacuum behind the truck still sucks dust into the camper shell, Ya just can't win. Lets go racing.
