Hierarchy of controls for heights

Prevent the fall before you protect against it

Falls from height are among the biggest killers on Australian construction sites. Under Australia's model WHS laws you don't get to pick whichever control is easiest — you must work down the hierarchy, starting with the most protective option, and only move to a lower level when a higher one isn't reasonably practicable.

Try firstTry last

1 · Eliminate — do the work from the ground

2 · Passive fall prevention — barriers

3 · Travel restraint — can't reach the edge

4 · Fall arrest — catch the fall

5 · Admin controls & PPE

This unit assesses work above 2 m — but the hierarchy applies to any risk of a fall. Your chosen controls, and why you chose them, go into the SWMS before work starts. Step through each level, take the quick check, then screenshot the summary.

1

Most effective

Eliminate the risk

Don't work at height at all. If the fall can't happen, nothing else on this list is needed — no gear to inspect, no rescue plan, no one hanging in a harness.

Trusses built on trestles at ground level, then craned into position — nobody leaves the ground.

On site this looks like

Prefabricate on trestles at ground level Extension poles & tools used from below Assemble low, crane into place Lower the work — not the worker

Ask it first, every time: can this task be done from the ground? If yes, the fall risk never exists — and that beats managing it.

2

Passive fall prevention

Barriers that protect everyone

If you must work at height, put a physical barrier between every worker and the fall — one that works without anyone having to hook on, remember a rule or follow a procedure.

Edge protection on the slab; a scissor-lift EWP with its own guard-railed basket beside it.

On site this looks like

Guard rails Edge protection Scaffolding Elevated work platforms (EWPs) Stairways instead of ladders Trestle platforms with rails

Passive means no one has to do anything for it to work. Scaffold, rails and barriers must be properly installed — and certified where required — before anyone works behind them, and they stay in place for the whole job.

3

Work positioning

Travel restraint

A harness and a fixed-length line to an anchor point, set so you physically cannot reach the fall edge. The restraint technique still prevents the fall — it just relies on correct set-up.

The lanyard goes taut before the worker reaches the edge — the fall is prevented, not caught.

On site this looks like

Anchor points Full-body safety harness Fixed-length restraint lanyard Static line rigged for restraint Temporary anchor systems

Set the line length so you cannot reach the edge — including corners. If you can get to the edge, you're not in restraint any more: you're relying on fall arrest, one level lower. Traverse between anchor points while staying connected the whole way.

4

Lower-order control

Fall arrest

Fall arrest doesn't prevent the fall — it catches you after it starts. Harness, energy-absorbing lanyard or inertia reel, connected to a rated anchor or static line. Use it only when the higher levels aren't reasonably practicable.

The fall happens — the system limits how far and how hard. There must be enough clear space below to arrest it.

On site this looks like

Fall arrest anchors Inertia reels Energy (shock) absorbers Harness + lanyard, snap hooks & karabiners Static line systems Rescue equipment on standby

Before anyone hooks on: inspect every component and report defects, confirm fall clearance below, connect without being exposed to a fall — and have a rescue plan ready. Suspension in a harness after an arrested fall becomes dangerous within minutes.

5

Last resort — never alone

Administrative controls & PPE

Rules, signs, barricades and personal gear. These depend on every person doing the right thing, every single time — which makes them the least reliable level of the hierarchy.

Signage, barricades and an exclusion zone around the drop area — plus the SWMS and PPE that back everything up.

On site this looks like

Signage Barricades & exclusion zones SWMS & toolbox talks Permits & supervision PPE — hard hat, boots, gloves

These support the levels above — they never replace them. A sign doesn't stop a fall, and a hard hat protects the people below from dropped tools, not the person on the roof. If admin and PPE are all you've got, stop and rethink the job.

Quick check

Three fast calls. Pick the answer a heights-savvy worker would give.

1. A bracket needs fixing at the top of a 6 m wall. What should you ask first?

Elimination comes first, every time. If the task can be done from the ground — prefabrication, extendable tools, installing from below — the fall risk disappears entirely.

The hierarchy at a glance

📸 screenshot me

1

Eliminate

Do the work at ground level — the fall can never happen.

Prefabricate on trestles · extendable tools · assemble low, crane into place

2

Passive fall prevention

Physical barriers that protect everyone, hands-free.

Guard rails · edge protection · scaffolding · EWPs · stairways · railed trestles

3

Travel restraint

Harness + fixed-length line so you can't reach the edge.

Anchor points · restraint lanyard · static line rigged for restraint · temporary anchors

4

Fall arrest

Catches a fall that's already happening. Needs clearance + rescue plan.

Inertia reels · shock absorbers · fall arrest anchors · static lines · rescue gear

5

Admin controls & PPE

Backs up the levels above — never replaces them.

Signage · barricades & exclusion zones · SWMS & toolbox talks · hard hat, boots

Prevent the fall before you protect against it. Only drop a level when a higher control isn't reasonably practicable — and record your choice, and why, in the SWMS.

CPCCCM2012 Work safely at heights · Australia's model WHS laws ·