(1) The school and school site must be maintained free of harborage for insects, rodents, and other vermin. Extermination methods and other measures to control insects and rodents must conform with the requirements of the department or the local health authority.

(2) All areas must be maintained free of accumulation of debris or standing water which may provide rodent harborage or breeding places for flies, mosquitoes, and other pests.

(3) Whenever potential for rodent infestation exists, storage areas must be maintained so as to prevent rodent harborage. Lumber, pipe, and other building materials must be stored neatly at least one foot above the ground.

(4) Whenever the potential for insect and rodent infestation exists, building construction must be of a type which will not provide harborage. The growth of brush, weeds, and grass must be controlled to prevent harborage of noxious insects and other vermin. School grounds must be maintained to prevent the growth of noxious weeds considered detrimental to health.