The screened environment of laboratory animal institution is an isolated system at dynamic running. When people, animal, feedstuff, air, padding and articles enter into this area, strict microorganism control should be carried out. If the equipment control element of transferring compartmeni, aqueduct, anemon-showering cave and buffer cave are lack of necessary door forbiden auto control equipment, it may causes fault work and lapses facility in daily work. This door forbidden system can control the time and the switch program of equipments, and start disinfection.