01Fall height and critical fall height
The free height of fall is the distance from where a child stands, sits or holds on to the surface below. The equipment manufacturer states it in the product documentation.
The critical fall height is a property of the surface. It is the greatest height at which the falling headform test of EN 1177 gives a head injury criterion HIC of 1000 or less and an acceleration of 200 g or less. A surface is suitable when its critical fall height is at least the equipment's free height of fall.
02Where a soft surface is required
Under EN 1176-1 an impact-absorbing surface is needed under equipment with a free height of fall above 0.6 m. Grass works up to roughly 1–1.5 m; above that, sand, gravel, bark or a synthetic surface with a critical fall height tested to EN 1177 is laid. The maximum free height of fall for playground equipment is 3 m.
A seamless rubber surface does not scatter or need topping up, which is why it is chosen for busy playgrounds and accessible areas.
03Impact area
The surface is laid around the equipment, not only beneath it. The impact area extends at least 1.5 m beyond the equipment, and for fall heights above 1.5 m by two thirds of the height plus 0.5 m.
| Free height of fall | Impact area beyond the equipment |
|---|---|
| up to 1.5 m | 1.5 m |
| 2.0 m | 1.85 m |
| 2.5 m | 2.2 m |
| 3.0 m | 2.5 m |
Swings and other equipment with forced movement need a larger area; its size is given in the product documentation.
04How thickness affects protection
The critical fall height rises with the thickness of the shock-absorbing layer. In seamless Teping coatings the lower layer of black SBR granules absorbs impact, and the upper EPDM layer provides colour and wear resistance.
- Under play equipment, the two-layer Teping Sport Combi is chosen: the recommended thickness is 12–20 mm, and the lower layer is made thicker under tall equipment.
- Single-layer Teping Sport EPDM, from 10 mm thick, suits paths, courts and areas without falls.
- The layers are bonded with the polyurethane binder Teping AD RC. Layer-by-layer build-ups and consumption are in the Sport EPDM and Sport Combi systems.
05What to send us for a calculation
- Take the free height of fall of each item from the equipment documentation.
- Mark the impact areas on the plan using the table above and work out the area.
- Describe the base: concrete, asphalt or soil with crushed stone.
- Send us these details and we will propose the layer build-up and thickness for your playground.
The finished surface can be checked on site: EN 1177 also describes a test at the place of installation.
Sources. Based on the instructions and technical data sheets for Teping® products published at tnpgroup.ru and the TNP technical solutions album 2025. Always follow the instruction for the specific product and batch.
