All impact windows go through an impact test before they can be approved and distributed. They shoot a projectile at high speed towards the window to see if the window can withstand it. The windows used are the same product that will be sold to the public. The two panes of laminated glass and the inner polyvinyl butyral frame that keeps it together. For storms, impact windows are tested in a room that simulated the pressures felt in a storm. All windows have to withstand up to 190 mph winds to be approved. Once they pass both tests is when the window can be used for homes.