There is no blasting with any type of media which won’t do some damage to the finish. Sometimes different cleaners and detergents are effective. There are chemicals that can also be used. If the door has to be repainted, we would recommend a very light brush blasting for adhesion and then a repaint. If the door is always getting tagged with graffiti, we can apply an invisible Nano coating that allows you to wash it off with warm soap and water. This will work about 4 times before a reapplication of the coating will need to be reapplied.