In or der to e nsure normal teaching or der, prote cting st ude nts ' healthy growt h, e nsuri ng that national (property) is not lost, t o preve nt or minimize the occurre nce of safety acci dents, follow the "preve nt, rescue each other, e nsure safety and reduce l osses" pri nci ple, a ccor ding t o the l ocal conditi ons, make t he manageme nt system. 1, the principal i s the re sponsi bility