Is Liquid Rubber Waterproof Sealant safe for drinking water? Currently we do not have a certification allowing this use. Related articles Does the product have a detrimental impact to fish or aquatic plants? Can I use RV Roof Coating on a Metal Trailer Roof? How should I prepare the surface before applying Waterproof Sealant? How do I cover gaps and cracks? The black surface turns brown when wet? Comments 0 comments Please sign in to leave a comment.