E 
		
				
			
		ecc83
Well-known member
One idea comes to me, a very 'stiff' door mechanism. A small supermarket near me has a door that takes considerable heft to open even from my 6ft 17st frame! It is equally slow to close. A door that take 5-6 seconds to open and close again will generate little air noise. 
Dave.
				
			Dave.
 
 
		 Or the twilight zone.
  Or the twilight zone. 
 
		 
 
		
 
 
		 
 
		 
 
		 
 
		