Ceramic Tile

Ceramic tiles are used in a variety of applications including on floors or walls for commercial, light commercial, institutional, and residential applications. Ceramic tiles are made primarily of natural materials including clay, feldspar, and sand. They are fired at very high temperatures (approximately 2000-2200F). Because of this high temperature processing, they are typically considered inherently non-emitting materials. Backing or coating materials applied after firing may contribute additional content and volatiles but were not found to be common. The content information is commonly provided in terms of the raw materials combined to make the ceramic tile and is therefore provided as such here. The firing process alters the structure of the material. Information on the oxide content of the finished tile is provided in the All Contents tab. 

Ceramic tiles can either be porcelain or non-porcelain. Porcelain tiles may contain more refined materials and are fired at higher temperatures for longer times. They are more dense and have lower water absorption than non-porcelain ceramic tiles and are therefore often recommended for areas that see more moisture, like bathrooms. Porcelain tiles tend to be more expensive, and because they are more dense, can be harder to work with, but they are more durable and therefore recommended for high traffic applications. Both non-porcelain and porcelain ceramic can be either glazed or unglazed. 

Many tile manufacturers recycle scrap unfired and fired tiles from their own production back into the manufacturing process. This content is included below as the same raw materials. Some manufacturers incorporate additional recycled content. Post-consumer recycled content may include glass or ceramic tiles. Pre-consumer recycled content may include granite or other mineral dust or ceramic scrap from other products such as toilets. The type of recycled content in products is not always disclosed. Some other types of recycled content that have been researched but may or may not be used in products at this time include post-consumer cathode ray tube materials or industrial waste such as fly ash or municipal incinerated bottom ash. Cathode ray tubes may be used in several countries, including the U.S. and are a particular concern because they contain high levels of lead that may be dispersed during processing or when the resulting tiles are cut or abraded. 

Roughly 30% of tiles used in the United States in 2018 were domestically manufactured. The countries providing the most ceramic tile to the US include China, Mexico, Italy, Spain, and Brazil. Tariffs since imposed on imports may have shifted this mix. US manufacturers have largely phased out the use of lead and other toxic heavy metals in glazes. It is unclear if this trend is also taking place in other regions. Given that lead has historically been used in ceramic glazes, and cookware products imported from various locations including China, Mexico, Italy, and Spain have been recently found by the FDA to contain excess lead, it is estimated that lead-based glazes may still be common in ceramic tile manufacture outside of the United States. Lead and other heavy metals in glazes may be released as part of dust generated when tiles are cut or abraded. In addition, if a glaze is not properly formulated or fired, lead and cadmium have been shown to leach into food from ceramicware products, and therefore may leach out of ceramic tile glazes under certain conditions as well. 

Manufacturers prescribe wet cutting methods or the use of manual cutting tools during installation to reduce the generation of dust and potential exposure to silica dust and toxic metals. Integral dust collection on equipment or local exhaust ventilation is also recommended when cutting grinding or removing ceramic tiles.