Edge Protection — Guardrails and Stopping Falls on Trade Sites (2026)

What Edge Protection Actually Is

Edge protection is a collective fall-prevention measure: a physical barrier fitted at an open edge to stop people and materials falling. In practice that means guardrails, intermediate rails and toe boards installed around the edges of roofs, floors, stairwells, scaffolds, excavations, mezzanines and openings — anywhere someone could step, slip or be pushed over a drop.

The key word is collective. Edge protection works for everyone on site without anyone having to do anything. Unlike a harness, it does not depend on an individual clipping on correctly, choosing the right anchor point, or remembering to wear it. Put a guardrail up and it protects the labourer carrying a board, the visiting surveyor, and the apprentice who has never been on a roof before. That is why it sits so high in the hierarchy of controls.

Where Edge Protection Sits in the Law

The Work at Height Regulations 2005 set out a clear hierarchy. You must work through it in order — you cannot jump to the bottom because it is cheaper or quicker.

• Avoid working at height altogether where you reasonably can — assemble at ground level, use extendable tools from below.
• Prevent falls using collective protection first — guardrails, edge protection, working platforms and scaffolds. Only where this is not reasonably practicable do you move to personal fall protection such as work-restraint or fall-arrest harnesses.
• Mitigate the consequences of a fall with collective measures such as safety nets or airbags, and only then personal fall-arrest systems.

Edge protection lives at the top of the "prevent" tier. The regulations explicitly require you to give collective protection measures priority over personal protection measures. If an inspector finds your team in harnesses on a roof that could reasonably have had guardrails, you have got the hierarchy the wrong way round — and that is a common reason for enforcement action.

The Guardrail Dimensions the Law Requires

This is the part every trade business owner needs committed to memory, because inspectors carry a tape measure. The Work at Height Regulations and the supporting scaffold standards set out specific minimums for any guardrail system protecting an open edge.

• Main (top) guardrail: at least 950mm above the edge or working surface. Measure from the platform or surface a person stands on, not from the floor below.
• Intermediate guardrail or other protection: positioned so that no unprotected gap exceeds 470mm. With a top rail at 950mm you will typically need at least one intermediate rail to close the gap.
• Toe boards / barriers: fitted at the edge to stop tools, materials and debris falling onto people below. A toe board of around 150mm is standard, though the test is whether it actually prevents materials rolling or being kicked off the edge.

These are minimums, not targets. A top rail that has sagged to 900mm, an intermediate rail left off, or a missing toe board at a busy edge are all defects an inspector will write up — and each represents a real route to a fall or a dropped load.

Why Collective Protection Beats Personal Protection

Some operators default to harnesses because they are cheaper than a scaffold or an edge protection system. That logic gets the priorities backwards and, frankly, gets people hurt. Here is why guardrails win every time it is reasonably practicable to use them.

• It protects everyone, not one person. A guardrail covers anybody who walks past the edge. A harness only protects the person wearing it, correctly, clipped to a rated anchor.
• It needs no decisions in the moment. Once installed, a guardrail works passively. Personal fall-arrest relies on the user selecting the right anchor, setting the right lanyard length, and avoiding pendulum and free-fall distance miscalculations.
• A harness stops a fall; it does not prevent one. Fall-arrest still means hitting the end of a lanyard, with injury risk and the danger of suspension trauma if rescue is slow. Edge protection stops the fall happening at all.
• It demands a rescue plan. Anyone using fall-arrest needs a workable plan to recover a suspended worker quickly. Guardrails carry no such burden.

Harnesses still have their place — short-duration work on a complex roof where guardrails genuinely cannot be installed, for example — but they are the fallback, not the first choice.

Types of Edge Protection

Edge protection is not one product. The right system depends on what you are protecting — a slab edge, a scaffold lift, a pitched roof — and how the load will be resisted.

Proprietary Temporary Edge Protection (BS EN 13374)

For temporary work, particularly on roofs and slab edges, the relevant standard is BS EN 13374, which classifies edge protection systems by the loads they must withstand. The class you need is driven mainly by the angle of the surface — a steeper pitch means a falling person arrives with more energy, so the system must be more robust.

• Class A: resists static loads only — suitable for flat or near-flat surfaces where a person would fall against the barrier rather than slide down into it.
• Class B: resists static plus low dynamic (impact) loads — for steeper surfaces up to around 30 degrees.
• Class C: resists higher dynamic loads from someone sliding down a steep pitch — for the steepest roofs, up to around 60 degrees, where the barrier must catch a sliding body.

Scaffold Guardrails

On a tube-and-fitting or system scaffold, the guardrails are an integral part of the structure — top rail at 950mm minimum, intermediate rail to keep any gap under 470mm, and a toe board at every working lift. These must be in place before the platform is used, not added afterwards.

Free-standing and Counterweighted Systems

On flat roofs and slab edges where you cannot or do not want to fix into the structure, free-standing counterweighted guardrail systems use weighted bases to hold the barrier upright. They are quick to install and leave no fixings behind, which makes them popular for maintenance and short-duration roof work.

Embedded and Clamped Post Systems

On concrete slab edges during a build, post sockets cast into the slab or clamp-on systems gripping the slab edge provide guardrails for the duration of the floor. These give a strong, permanent-feeling barrier while the slab edge remains open, and are removed as the permanent edge or cladding goes in.

Fragile Surfaces and Rooflights

Fragile surfaces deserve their own warning because they cause a steady stream of deaths that edge protection at the perimeter does not address. Old asbestos cement sheets, fibre-cement roofs, corroded metal sheeting and rooflights can all fail under a person's weight with no warning.

A rooflight is often the same colour as the surrounding roof once it has weathered, so it disappears into the surface — a worker steps onto what looks like solid sheeting and falls straight through. Treat every rooflight as fragile unless you have firm evidence otherwise. Protect them with covers, guardrails or barriers around each one, or with properly designed crawling boards and platforms that span the fragile area. Never rely on a worker simply remembering where the rooflights are.

Inspecting Scaffolds and Edge Protection

Putting edge protection up is only half the job — it has to stay correct, and the law requires inspection. A scaffold from which a person could fall 2 metres or more must be inspected by a competent person:

• Before first use, after it is erected or substantially altered.
• At regular intervals not exceeding 7 days while it remains in use.
• After any event likely to have affected its stability — high winds, an impact, or other adverse weather.

The results must be recorded, and the record kept on site until the work is complete. The same principle of regular checks applies to other edge protection: a system that was perfect on Monday is no good if a lift removed the rails on Wednesday and nobody put them back. Build a quick guardrail check into your daily site walk.

CDM 2015 Duties and Competence

The Construction (Design and Management) Regulations 2015 spread responsibility for safe work at height across the project. Designers should design out the need to work at height where they can and flag residual risks. The principal contractor and contractors must plan, manage and monitor the work, including providing and maintaining edge protection.

Crucially, CDM 2015 requires that everyone involved has the skills, knowledge, experience and — for organisations — the organisational capability to do their part safely. Anyone erecting, altering or inspecting scaffolds and edge protection must be competent to do so. Sending an untrained operative up to "sort the rails out" is exactly the kind of thing that turns a near miss into a fatality and a prosecution.

Common Failings That Catch Trade Firms Out

Most edge protection enforcement does not come from firms that never bother — it comes from firms that had protection but let it slip. Watch for these:

• Incomplete guardrails: a top rail fitted but no intermediate rail, leaving a gap well over the 470mm maximum.
• Removed and not replaced: rails taken off to load out materials or pass a window in, then forgotten. This is the classic cause of falls on otherwise well-run sites.
• Gaps at gable ends and corners: protection that runs along the eaves but stops short at the gable or a return, leaving an open edge exactly where people work.
• Missing toe boards: guardrails present but nothing to stop tools and offcuts being kicked onto people below.
• Wrong class for the pitch: a Class A system used on a steep roof where a sliding fall needs Class C.
• No inspection record: protection in place but no 7-day inspection logged, so you cannot show it stayed compliant.

Quick Reference: Edge Protection Requirements UK 2026