When reading the different marketing literature pieces that accompany many ceramic tile products you’ll notice a section that is usually placed toward the back that is often referred to as “technical specifications”. This can often be a confusing set of codes and numbers but they are important pieces of information to understand when buying ceramic tile. Both ANSI (American National Standards Institute) and ASTM International have developed standard testing methods and the results are often noted in the technical specification section. This article is designed to help sort out the meanings of some of the more important technical properties that you will want to be aware of and will often be identified in the technical specification section.
Slip Resistance. This is often referred to as coefficient of friction (COF) and it refers to the relative slipperiness of a tile. The tile industry transitioned from a somewhat unreliable test method to a more accurate method of testing in 2012. Therefore, you may find technical specifications using the old method as they had not been updated. The old method, called SCOF (Static Coefficient of Friction), had a dry value and a wet value where it was suggested that any wet value of >.60 was preferred.
The newer, consistent method, DCOF (Dynamic Coefficient Of Friction) AcuTest, is much more accurate and has only one value which is a measurement of when the tile is wet. As stated by the TCNA (Tile Council of North America) ANSI A137.1-2012 says that “ceramic tiles selected for level interior spaces expected to be walked upon must have a minimum wet DCOF AcuTest value of > 0.42. Tiles with a lower value are not necessarily restricted to dry areas only, but rather are restricted to applications where they are kept dry when walked upon. In the case of residential bathrooms, the common use of bathmats can accomplish this. Similarly, in entranceways, the use of entrance mats can accomplish the same.
Note that in some technical specification charts either “pass” or “fail” will be noted under the DCOF heading. A tile passes if the value achieved is >0.42.
Moh’s Hardness. To give the consumer a relative measurement of scratch resistance of tile and stone, manufacturers and suppliers use the Moh’s Hardness Scale. The Moh’s scale uses ten fairly common minerals of known hardness and gives each of them a relative value of 1-10. Each mineral in the scale will scratch those with lesser values and will not scratch those with higher values. As you can see by the Moh’s scale below, Talc has the lowest classification and the softest mineral on the list and Diamond has the highest and is the hardest mineral known. To better illustrate the hardness of tile, take note that case-hardened steel, which is used in drill bits to drill holes in steel, is a 6 on the Moh’s Hardness scale.
|Moh’s Hardness||Mineral||Compared to other flooring Materials|
|1||Talc||resilient flooring (vinyl, asphalt tile)|
|3||Calcite||polished marble, laminate flooring|
|5||Apatite||glazed ceramic tile|
|6||Feldspar||glazed ceramic tile|
|7||Quartz||quarry tile, glazed porcelain tile|
|8||Topaz||unglazed porcelain tile|
|9||Corundum||no flooring is this hard|
|10||Diamond||no flooring is this hard|
Abrasion resistance. To better help consumers identify the appropriate tile products for their particular application in regards to how they will wear to foot traffic; the tile industry developed the “visible abrasion classification” system. Often this is referred to on technical specifications as “abrasion resistance”, “durability classification” or “PEI rating”. It’s a scale of 0 – 5 that indicates how a floor tile will wear due to the amount of foot traffic and therefore suggest what floor applications (if any) that the tile is appropriate for. All tiles are independently tested for their abrasion resistance in accordance with testing procedures developed by ASTM (American Standard Testing and Materials).
|Class 0||Not recommended for floors. Walls Only.|
|Class I||Light Residential – for residential bathroom floors only|
|Class II||Residential – residential interiors with the exception of kitchens, stairs, landings and areas near external entries.|
|Class III||Heavy Residential and Light Commercial – all residential applications. Commercial applications which are similar in traffic to residential application. Specifically excepted are areas of prevalent circulation or turning points.|
|Class IV||Commercial – all residential and most commercial applications such as the public areas of exhibition halls, hotels, restaurants, supermarkets, shops and schools.|
|Class V||Heavy Commercial – all residential and commercial applications such as airports, shopping malls, and other heavily traffic public spaces.|
Frost Resistance. If you are planning on installing ceramic tile outdoors and you live in a temperate zone that experiences freeze/thaw conditions, you’ll want to only select a tile that is suitable for outdoor installation where there is a freezing and thawing cycle. Note: If you are planning on installing tile horizontally (floor) outdoors we highly recommend you also pay close attention to the slip resistance of a tile.