No VOC Use the Earth Safe Sinishes Sealers to seal porous surfaces, forming a barrier to keep anything on the ?inside? from bleeding through and anything on the ?outside? from penetrating back through the surface. A sealer is the first step in ensuring that what you paint, stain, or decorate maintains the look you want and doesn?t deteriorate over time. Our sealers can be used on wood, keeping the moisture from green wood from seeping through. A non-toxic water-based sealer that completely seals furniture, new or old wood, cabinets, craft projects, walls ? inside or outside, wood floors, terra cotta, cement, brick, concrete and more. Keeps the internal moisture in and the external wetness out. The Sealer seals knots in the same way.