Technical Services


Crossville adopts the new standard for measuring coefficient of friction

Our products now feature both COF and DCOF ratings to help determine suitable tile products for commercial applications

Crossville Inc. is excited to adopt the new DCOF AcuTest™ for determining product suitability for commercial environments. We are among the first in the tile industry to implement this new industry standard on all of our product collections.

So, what does the new DCOF AcuTest mean?
Here´s the background:

Friction is the force that resists the sliding motion of one surface against another, such as the motion of a shoe slipping on a floor. Contaminants, such as liquids, oil, dirt and debris, can alter the friction.

The Top 5 Things you need to know about DCOF.
  • The DCOF AcuTest measures DCOF, not SCOF. DCOF is more widely used worldwide, and offers measurements for conditions when walking on tile.
  • All Crossville products have been tested using both methods. You can obtain these measurements by contacting Crossville Customer Service at 931-484-2110.
  • DCOF AcuTest uses slightly soapy water instead of clean water for testing.
  • .42 wet is the new measurement standard for the DCOF AcuTest
  • The DCOF AcuTest is included in the latest version of ANSI A137.1 Specifications for Ceramic Tile.

There are two types of friction: static (SCOF) and dynamic (DCOF). SCOF is the ratio of forces necessary to start two surfaces sliding. This is what the former ASTM C1028 static test measured. DCOF is the ratio of forces necessary to keep two surfaces sliding. The new DCOF Acutest measures this ratio; it is more widely used worldwide and relates better to slips occurring while a person is in motion.

Because of the two type of friction, it is now measured on two scales (DCOF and SCOF). The new .42 wet (DCOF) is now used in conjunction with the old reference of .60 COF wet, which has long been the benchmark for friction in commercial flooring applications.

The new, more stringent DCOF AcuTest uses a portable robot (the BOT 3000), an SBR rubber sensor and slightly soapy water (0.05% sodium, lauryl sulfate solution) to measure dynamic friction. The advantage of this measurement is that it is a repeatable, reproducible method for measuring slip potential. According to the TCNA, it is a big improvement over the old test method. It also offers a standardized minimum threshold, which is new to the industry.

As the tile industry continues to transition to the new DCOF test, Crossville will provide both SCOF and DCOF scores for all Crossville flooring products to help you determine the right product for your project. It is important to note, however that not all products with a DCOF value over 0.42 are suitable for all applications. Type of use, expected traffic and wear, contaminants, maintenance, and manufacturer guidelines must also be considered when specifying a product.

To see a comprehensive chart showing SCOF and DCOF of Crossville products, please click here

For more information on DCOF, visit TCNA´s website at or contact your Crossville Technical Service Team.