The four systems at a glance
| System | Position | Fixed to | Purpose | Typical site use |
|---|---|---|---|---|
| S | Horizontal | Structure, via the border rope | Catches falls | Below steel decks, roofs, bridges |
| T | Horizontal | Brackets at the edge | Catches falls | Slab and roof edges |
| U | Vertical | Supporting frame | Prevents falls | Open edges, scaffold sides |
| V | Vertical, hung | Gallows-type arms | Catches falls | High-rise concrete frames |
System S
A System S net is a net with a border rope, fixed horizontally to the structure with tie ropes. It is installed below the area where people work, so anyone who falls lands in the net. Because it needs anchor points around the area to protect, it suits structures with beams, columns or slabs at the right level: steel frames, roof structures, bridge decks, long-span halls. EN 1263-1 sets a minimum net size for System S, and larger areas are covered by joining several nets. Read more on the construction safety nets page.
System T
System T nets are fixed to brackets for horizontal use. The brackets are mounted on the edge of a slab or roof and the net is stretched over them so it projects outwards. It catches people falling over the edge where there is nothing below to fix a System S net to. The width of the net must give enough catching width for the fall height. See bracket safety nets.
System U
System U nets are fixed to a supporting framework for vertical use. Together with the posts or frame, they form a barrier at an open edge. This is prevention rather than arrest: the net stops the person before the fall begins. System U is used at slab edges, roof perimeters, stair openings and scaffold sides. Temporary edge protection systems as a whole are covered by EN 13374. See edge protection nets.
System V
System V nets have a border rope and are hung from gallows-type supports fixed to the building. The top of the net rises above the working floor, the bottom is tied to the floor below. As the building rises, the arms and nets are lifted floor by floor. It is the standard solution on concrete frame towers where a full facade scaffold would be slow and costly. See System V safety nets.
How to choose
- Can you prevent the fall? If an edge can be closed, use edge protection (System U or guardrails).
- Is there structure below the work? If yes, use System S as close as possible below the working level.
- Is the risk at the perimeter with nothing below? Use System T on brackets.
- Is it a high-rise frame built floor by floor? Use System V.
- Must small objects be caught? Add a debris net to any of the above.
Many sites use several systems at the same time. The complete safety net guide explains classes, installation and inspection for all of them.
Frequently asked questions
Which EN 1263 system is most common?
System S, the horizontal net with a border rope fixed directly to the structure, is the most widely used, especially under steel structures, roofs and bridge decks.
Can one net be used in different systems?
No. Each net is designed, tested and labelled for its system. Use the net only in the system shown on its label.
Is System U a fall arrest net?
No. System U is used vertically to prevent falls at an edge. Systems S, T and V catch falls.