In or der to e nsur e normal teachi ng or der, prote cting st ude nts ' he althy growt h, e nsuri ng that national (property) is not l ost, to prevent or minimize t he occurrence of safety acci dents, follow t he "preve nt, rescue ea ch othe r, ensure safety and re duce losse s" principle , according to t he local conditi ons, make t he manageme nt system. 1, t he principal is the responsi bility