Afm Safecoat Safe Seal, White Gallon Can 1/Case This multi-use, water-based, low-gloss sealer works for highly porous surfaces such as particleboard, plywood, processed wood and porous concrete. This sealer is used primarily to reduce toxic outgassing. It is highly effective at sealing in formaldehyde outgassing from processed wood such as plywood, particleboard and pressed wood.