One way to try and keep dust down and out of the interior of ones trailer is that when travelling, crack open the rear half of the rearmost vent cover while towing. By doing this the interior of the trailer has a positive pressure and will "force out" small minute openings because of the positive
pressure. When a trailer is all closed up, it typically will actually pull a slight vacuum which means that dust and dirt particles are pulled into the trailers through minute openings.

For most travelling this scenario is not apparent but when one travels a very dusty road then it becomes quite obvious. This is particularly true in the vintage units which have many more minute openings than newer ones.

Just a thought........

Tom H.
WBCCI # 6490
'53 Airstream Flying Cloud