Fog Seal is a preventive maintenance technology that sprays high permeability modified emulsified asphalt on the surface to close road pores, prevent the infiltration of rain, repair aging roads, improve the appearance of the road. Fog Seal is generally used for mild to moderate fine or loss of loose material on the road. When the open-graded mixture appears loose, the fog closed layer can be effectively resolved. The main technical advantages: First, it can prevent from oxidation of the old pavement and be updated. The second is to fill small cracks and gaps. Third, widening the asphalt pavement and expanding the contrast of marking. Fourth,  prevention loose of the open-graded road. Fifth, the construction speed of traffic and opening up quickly. Sixth, construction costs lower.