The following information is designed to help assess the depth and area size of safety surfacing required.
Depth of surfacing
The depth of surfacing required is calculated according to the Free Fall Height (FFH) of any play equipment, along with the surface's Critical Fall Height (CFH). This is the height from which it is assessed that a surface will absorb the impact of a child's fall sufficiently to reduce the risk of serious head injury.
The maximum FFH (ie the distance between any accessible part of play equipment intended for play and the surface beneath) should equal or not exceed the surface's CFH.
Stationary equipment
For equipment on which a child stands, the FFH is calculated from the highest point on the equipment which is intended for play - usually the platform height. For equipment from which a child hangs, the height of the hand support is used.
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Swings
The FFH is calculated from the centre of the stationary seat surface at 60 degrees. To work this out divide the length of the chain by 2 then add the distance from the seat to the ground.
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Area of surfacing
The extent of surfacing required around the play equipment is dictated by the height of any potential fall.
Stationary equipment
For stationary equipment with a FFH of 1.5m or less, surfacing should extend at least 1.5m beyond the edge of the equipment. To calculate the surfacing distance for equipment with a FFH of over 1.5m, substract 1.5m from the FFH and multiply the result by 0.667 before adding back the 1.5m. The table below demonstrates this principle.
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Swings
The area of surfacing required is calculated as follows:
- To calculate the the length of surfacing required to the front and back of the swing, multiply the length of the chain by 0.867 then add 1.15m.
- The width of surfacing required for seats no greater than 500mm width is 1.75m (ie 0.875mm each way from the seat centre). For swings with seats wider than 500mm the difference between the seat width and 500mm must be added to the 1.75m (50% to each side of the swing centre). Please note that areas for two seats in one bay may overlap providing the distance between seats in 20% of the swing chain +300mm.
RTC's surfaces
RTC Safety Surfaces have been tested according to British and European Safety Standards to the certified levels below.
![]()
Please note that if the sub-base is Type 1 MOT stone the minimum depth which can be laid is 40mm.
The following information is designed to help assess the depth and area size of safety surfacing required.
Depth of surfacing
The depth of surfacing required is calculated according to the Free Fall Height (FFH) of any play equipment, along with the surface's Critical Fall Height (CFH). This is the height from which it is assessed that a surface will absorb the impact of a child's fall sufficiently to reduce the risk of serious head injury.
The maximum FFH (ie the distance between any accessible part of play equipment intended for play and the surface beneath) should equal or not exceed the surface's CFH.
Stationary equipment
For equipment on which a child stands, the FFH is calculated from the highest point on the equipment which is intended for play - usually the platform height. For equipment from which a child hangs, the height of the hand support is used.
![]()
Swings
The FFH is calculated from the centre of the stationary seat surface at 60 degrees. To work this out divide the length of the chain by 2 then add the distance from the seat to the ground.
![]()
Area of surfacing
The extent of surfacing required around the play equipment is dictated by the height of any potential fall.
Stationary equipment
For stationary equipment with a FFH of 1.5m or less, surfacing should extend at least 1.5m beyond the edge of the equipment. To calculate the surfacing distance for equipment with a FFH of over 1.5m, substract 1.5m from the FFH and multiply the result by 0.667 before adding back the 1.5m. The table below demonstrates this principle.
![]()
Swings
The area of surfacing required is calculated as follows:
- To calculate the the length of surfacing required to the front and back of the swing, multiply the length of the chain by 0.867 then add 1.15m.
- The width of surfacing required for seats no greater than 500mm width is 1.75m (ie 0.875mm each way from the seat centre). For swings with seats wider than 500mm the difference between the seat width and 500mm must be added to the 1.75m (50% to each side of the swing centre). Please note that areas for two seats in one bay may overlap providing the distance between seats in 20% of the swing chain +300mm.
RTC's surfaces
RTC Safety Surfaces have been tested according to British and European Safety Standards to the certified levels below.
![]()
Please note that if the sub-base is Type 1 MOT stone the minimum depth which can be laid is 40mm.
