Grass Mat Standards

There are two types of test conditions – concrete base and field base tests.

The grass mat standard stipulates that all laboratory tests shall be carried out on a flat, rigid concrete. These are known as concrete base tests. Alternatively, they can be tested on a substrate of sufficient mass, density, and thickness without significant contribution to the results.

Installations with a combination of natural materials intended to influence their performance (e.g. soil) cannot be meaningfully tested in the laboratory. These tests – known as grass base tests – cannot be used to indicate the performance of the product under other conditions or in other locations. For example, surfacing installed and tested on clay-based soil. For this installation condition, it is likely to achieve a greater critical fall height when base is wet as opposed to dry.

When a supplier quotes a certification for a specific fall height that sounds too good to be true, they may have done a grass base test. You should always check with your supplier before buying. We recommend asking for proof of certification for concrete tests, as these will give the most accurate results.

Always remember to ask your supplier to clarify exactly what ground conditions their product has been tested on. For example, if the test states the mat was tested with a 140mm soil layer and mesh on a grass base, you will need to replicate these conditions on site in order for the grass mats to comply to their certification.