Onsite Slip Testing VS Lab Slip Testing

In practice, you will always find that there is a discrepancy between the slip resistance testing results that are found in the lab, and those that are found on site. Mostly, it is found that flooring materials or tiles have a lower slip resistance when they have been installed, when compared to that which they had when they were tested in the lab. There are several factors that lend themselves to this discrepancy, such that the results of a wet pendulum test done onsite will be different from that done in the lab.

Here are some of the reasons that could lead to such a difference:

  • The process of installation, where grouting has t be done and this brings about some wearing of tiles
  • The handling of the tiles when they are being installed, and the workmen walking over them
  • Some chemicals that may have been left over from the production process
  • Any cleaning that is done after installation
  • Environmental factors like rain or sunlight, where the floor is installed in an external area


In order to try to standardize the difference between the results of these two tests, the Accelerated Wear Test is performed on site. This is a test in which a series of wet pendulum tests is done before, during and after the installation of the floor. The tile is worn down by passing an abrasive pad over it and testing each time. The plot of the result of the pendulum test and the number of cycles that the pad has been passed over the tile, will give you the true slip resistance of the tile. It shows you the true way in which the tile will perform after it has been installed for a while.

The tiles are all different and you will see some difference in the Accelerated Wear Test results. This is quite common, where there is an initial sharp drop in slip resistance, and then it somehow flattens out. This is an indication that for most tiles, there is an initial drop in the slip resistance when they are instead, and then this will plateau out in the end. This is crucial since it can save you a lot in installing anti-slip treatments which may not be necessary after the loss of slip resistance stabilizes.

This test cannot be used to show the exact time frame that the slip resistance will stabilize. This is a factor of how much the floor is walked upon, the kind of shows that people will wear when on the floor and a lot more. A tile that is laid in the home will not have the same result as it would if it was installed in a busy shopping mall.

Slip resistance testing in the lab and onsite will always give different results for the same material. The Accelerated Wear Test tries to bring the two closer to each other. Talk to us now and we can explain the finer details of these two tests and ensure that your floors are safe.