What is the recommendation if soot staining remains on an unfinished wood surface?

Light sanding is the recommended approach for addressing soot staining on unfinished wood surfaces because it effectively removes both superficial stains and the layer of soot that can cling to the wood fibers. Soot consists of fine carbon particles that can embed themselves into porous materials like unfinished wood. When using light sanding, the goal is to carefully abrade the stained surface without damaging the underlying wood structure, allowing for the removal of the soot without worsening the stain.

This method is particularly suited to unfinished wood as it does not have a protective finish that could be compromised by other methods, such as chemicals or excessive moisture. Light sanding does not introduce additional substances to the wood that could cause further staining or damage, promoting a more straightforward, mechanical removal of the soot.

The other options may not be effective or could even harm the wood surface. For instance, vinegar may not be powerful enough to remove stubborn soot stains, while wet scrubbing risks further saturating the wood, leading to potential warping or other damage. Chemical cleaners might react adversely with the natural properties of the wood, especially without a protective sealant. Thus, light sanding is a practical and safe recommendation for this scenario.