The units are attached to a vacuum wall that attempts to suck the water being sprayed on the units through any seam or gaskets.
Design Pressure Testing
This test simulates the effects of Hurricane Force winds on Door and Window units.
A 2×4 projectile is fired multiple times at each test specimen with a phematic cannon. The test units must keep the projectile from penetrating through the unit and compromising the building envelope.
After the units are subjected to Impact Testing they are then put back on the vacuum wall and cycled with pressures that would be equivalent to those experienced in a hurricane or high wind event. This process lasts quite a while and at no point during this portion of the test can the units fail.
After all testing is complete, the units must still be operable.