This is the classification recognized by the ANSI for ceramics sold in the USA available to consumers. This system classified tiles as:

• Standard grade

• Second grade

• Wall tiles or decorating wall tiles.

Most of tiles sold in the States are standard grade and they meet the minimum requirement recognized by ANSI.

Second grade tiles are very similar to standard grade tiles the difference is in some imperfection which you can find on their glazes or sizes and consequently they are a little distant from their specification.

Second grade tiles are usually less expensive than a standard grade.

Wall tiles are tiles very thin: the body and glaze are so week that you can use those just as decorative without any functional use.

There is also a grading system again in the US called PEI wear rating system that gives costumers a more useful approach to choosing tiles.

The system divides ceramic tiles in five groups:

• Group 1: tiles for residential bathrooms floors

• Group 2: tiles for residential use but for areas where there is very low traffic like bedrooms and bathrooms.

• Group 3: tiles suitable for both; residential and light commercial use.

• Group 4: tiles appropriate for light commercial use like lobbies restaurant and hotels.

• Group 5: tiles suitable for serious performance traffic and damp areas like sidewalks and malls.

There are also angraded tiles different from graded tiles because they don’t meet the same values but not for this are less effective on the market, this tiles are row clay “cotto” or “saltillo” Mexican tiles.

Source: www.articlecity.com