The CANTY QSPL is the safest, quickest opening closure ever designed. What makes it unique is the method for door engagement. All other types of closures have doors that swing out or slide out away from the end of the reactor barrel in the same direction that the pressure force acts. If pressure is not completely relieved the door can blow open with great force and velocity and the potential for catastrophic injury to personnel. The QSPL slides out of the barrel at a direction perpendicular to the pressure force, and therefore the CANTY door never retains the potential
energy from the process pressure and can never be accelerated by residual pressure. Because the door moves perpendicular to the pressure a separate safety interlock is not required to meet ASME and PED standards.