While porcelain tile makes up over 70% of U.S. ceramic tile sales, some products labeled as porcelain don’t meet the strict ANSI A137.1 and ISO 13006 requirements, including the 0.5% water absorption standard. In this video, we explain how the Porcelain Tile Certification Agency (PTCA) verifies true porcelain tile—and why certification matters for manufacturers, distributors, and the industry.