Whether the oil on the warehouse or hanging, are willing to be stained with a layer of dust If the painting has dust coverage, the most scientific way to clean is to brush off the dust of the surface. But remember, before to sweep away the dirt you should make sure if the surface has been cracked or broken. If so, do not touch these parts. Oil painting should be avoid of wiping with a rag, and using with a wet cloth, it is also more dangerous. To use soapy water with a rag. Moisture will enter the delicate texture of the oil painting is difficult to come out, the older oil painting above there is a layer of light paint, and water and gas will produce a layer of gray after the lime effect, like bleaching the same work. Moisture can also lead to irregular shrinkage of the canvas, the pigment even more adverse adhesion. If the problem has been very serious, or to find professional advice.