Thermafiber® IMPASSE® curtain wall insulation system is a patented design that streamlines the installation of curtain wall insulation by changing the order of traditional installation steps to fit a more logical progression and take full advantage of the fire protective, sound control, and vapor barrier properties of FireSpan® and Safing™ Insulation. Traditional curtain wall insulation systems call for installation of impaling pins on spandrel panels before installation of insulation. The insulation is then impaled onto the pins. The Impasse system is unique in that the hangers are inserted into the insulation before the insulation is installed into the panels. This technique saves time and money. The Impasse® system is tested and rated with UL® laboratories and provides up to 3 hours of fire protection.