The best way to protect artworks that contain oil pastels is to frame the artwork behind glass or Plexiglass. Use a thick mat, such as a double mat, to keep the artwork away from the glass.
Answer: Placing a frame with glass in it will protect your acrylic painting from dust and dirt, as well as any accidental touches. If you're worried about sun damage, opt for a UV-protected plastic that looks similar to glass so your painting won't fade as easily.
