The work at height hierarchy of control
Every work-at-height decision follows one order of priority: avoid, then prevent, then minimise. Getting that order right is the difference between compliance and a harness used as a first resort.
The three levels
Regulation 6 of the Work at Height Regulations 2005 sets a strict order. You only move down a level when the level above is not reasonably practicable.
1. Avoid
Avoid working at height where it is reasonably practicable to do the work safely another way — for example assembling at ground level and lifting into place, using extendable tools from the ground, or fitting sensors and lights that can be maintained without going up. If the work at height can be designed out, that is always the first choice.
2. Prevent (collective before personal)
Where work at height cannot be avoided, prevent a fall. Prefer an existing safe place of work (a flat roof with permanent edge protection). Otherwise use collective protection that protects everyone without them having to do anything — guardrails, a scaffold with edge protection, a mobile tower, or a MEWP. Only where collective measures are not enough do you move to personal fall protection, such as a work-restraint system that stops someone reaching the fall point.
3. Minimise the distance and consequences
Where a risk of a fall still remains, minimise how far someone could fall and how badly they could be hurt — for example nets or soft-landing systems (collective), or a personal fall-arrest system with a harness and a planned rescue. This is the last resort, not the starting point.
Collective before personal
Within "prevent" and "minimise", there is a second rule: collective protection before personal protection. Collective measures — guardrails, edge-protected scaffolds, nets — protect everyone in the area without depending on each person. Personal measures — a work-restraint or fall-arrest harness — depend on the right anchor, correct use, training and a rescue plan, so they rank lower.
| Level | Aim | Examples |
|---|---|---|
| Avoid | Don't work at height at all | Ground-level assembly, extendable tools |
| Prevent | Stop a fall happening | Guardrails, scaffold, tower, MEWP; then work restraint |
| Minimise | Reduce fall distance/consequences | Nets, soft-landing systems; then fall-arrest harness + rescue |
The common mistake
The most frequent error is jumping straight to a harness. Personal fall-arrest sits near the bottom of the hierarchy — it is what you use when nothing higher is reasonably practicable, and only ever with a suitable anchor, training and a planned rescue. The right question is always "can we avoid or prevent first?", not "whose harness is this?".
Show the hierarchy in your RAMS
Complys builds work-at-height risk assessments and method statements that show how the hierarchy was applied, tracks IPAF/PASMA/harness training with expiry alerts, and holds equipment inspection records and rescue plans. Try the work-at-height checker, or keep it all in one place.
Work at height software →FAQs
What is the work at height hierarchy of control?
The order of priority in regulation 6 of the Work at Height Regulations 2005 for managing work at height: first avoid work at height; if it cannot be avoided, prevent a fall; and if a fall risk still remains, minimise the distance and consequences of a fall. You work down the hierarchy only when the level above is not reasonably practicable.
Why does collective protection come before personal?
Because collective protection — like guardrails or a properly edge-protected scaffold — protects everyone in the area automatically, without relying on each individual to wear, fit and use equipment correctly. Personal protection such as a harness depends on the right anchor, correct fitting, training and a rescue plan, so it sits lower in the hierarchy.
Is a harness the answer to working at height?
Not as a first resort. A personal fall-arrest harness is near the bottom of the hierarchy — used only where higher measures are not reasonably practicable, and always with a suitable anchor, training and a planned means of rescue. Reaching for a harness first is a common and serious mistake.
Related: what is work at height, Work at Height Regulations explained, and work at height software. General information, not legal advice.