An IP-rated transit case has a water and air-tight seal between lid or cover and body. That seal must be maintained in the face of relative movement caused by rough handling, pressure differentials between interior and exterior, and temperature extremes. That seal is formed by an O-ring. Continue reading
The greatest strength of the well-constructed transit case is also its greatest weakness. An airtight seal keeps moisture and dust at bay but can lead to a significant pressure differential. If the case becomes pressurized—say you close it at night and leave it in the desert sun all day—the sides might bulge, and the seal could give way. Continue reading
You’ve packed your delicate items in an airtight case to protect them from moisture and dust. Air can’t get in or out. That’s the purpose. But, what happens when the outside pressure changes?