Slate and stone tiles generally do not have a UL Mark. The Underwriters Laboratories (UL) primarily certifies electrical, fire, and safety-related products, focusing on materials and systems that pose inherent risks to electrical systems or fire safety. Slate and stone tiles, as non-electrical building materials, are not typically subject to UL certification unless they are part of a system tested for fire resistance or specific safety standards. However, most stone and slate tiles are not individually UL-certified.

UL certification requires rigorous testing against established standards, such as UL 723 for fire resistance or UL 447 for tile adhesives. While some manufacturers may voluntarily test stone or slate tiles for fire resistance under UL 723, this certification applies to the tile-adhesive system, not the tiles themselves. UL’s 2022 report indicates that only 3% of building materials carry UL Marks, predominantly for fire-resistant or electrical components. Stone and slate tiles are rarely included unless explicitly part of a tested assembly. For example, a tile installed with UL-certified adhesive might meet fire codes, but the tile alone lacks certification. Thus, the absence of UL Marks on most slate and stone tiles reflects their classification as non-specialized building materials not requiring UL-specific testing.