Dr Scaffold’s Advice: Using Energy Absorbing Lanyards Safely in Scaffolding

Energy absorbing lanyards are an important part of many fall arrest systems on scaffolding sites — but there’s a common misunderstanding about how much height you really need for them to work safely. Used in the wrong situation, they can give a false sense of security and put scaffolders in serious danger.

Here’s the straight truth from Dr Scaffold on when you should (and shouldn’t) use them, the alternatives to consider, and how the Work at Height Regulations 2005 apply.

What Is a Shock-Absorbing Lanyard?

A shock‑absorbing lanyard connects your harness to a secure anchor point via webbing or rope, with a built‑in energy absorber designed to limit the impact force if you fall. The absorber works by tearing or extending in a controlled way, reducing the sudden stop and lowering the risk of injury.

They come in single‑leg and twin‑leg versions — with twin lanyards providing 100% tie‑off, meaning you can stay clipped on at all times when moving between anchor points.

Fixed & Retractable Lanyards – Viable Alternatives

While shock‑absorbing lanyards are common, they are not the only option:

• Fixed length lanyards – Simple and light, but you must size them correctly to minimise potential free fall. They do not absorb energy, so they must be used only where anchor height and fall clearance are controlled.

• Retractable lanyards / fall arrest blocks – Self-retracting systems that keep the lifeline short and lock quickly in a fall. Many have their own energy-absorbing component and can drastically cut the fall distance — ideal for work where mobility is needed but clearance is limited.

The best choice depends on task type, available fall clearance, and required mobility.

The Real Clearance You Need for a Shock‑Absorbing Lanyard

This is the part most often misunderstood — it’s not just the 2 m lanyard length you need to account for.

A typical fall clearance calculation includes:

1. Lanyard length – usually around 2 m

2. Energy absorber deployment – typically 1.3–1.75 m in a fall

3. Harness stretch / worker’s body movement – allow about 0.5–1 m

4. Safety margin – minimum 0.5 m to avoid contact with the ground or obstruction

Total: In most cases, you need around 3.5–4 m of clear space below the anchor point.

If you have less than this, the lanyard will not fully deploy, meaning it will not absorb the impact correctly — you could still strike the ground or deck with dangerous force.

👉 Rule of thumb: Below 4 m clearance, use a shorter fixed‑length lanyard in restraint or a retractable block to prevent any fall rather than trying to arrest one.

The Law – Work at Height Regulations 2005

Under Regulation 6, you must:

• Avoid falls where reasonably practicable

• If there is a risk of a fall, either prevent it entirely or minimise the distance and consequence

• Only use fall arrest systems that are suitable for the task and conditions

• Consider clearance distance when selecting PPE — equipment must be able to function properly given the space available

Not considering clearance is not just unsafe — it can be a breach of the law.

Dr Scaffold’s Key Recommendations

1. Measure your clearance before selecting a lanyard — aim for 4 m or more for shock‑absorbing lanyards.

2. If you don’t have clearance, change the system — use restraint or a retractable to avoid the fall.

3. Use twin‑leg lanyards for continuous attachment when moving between anchors.

4. Inspect before every use and follow manufacturer lifespan rules (often around 5 years).

5. Ensure secure, tested anchor points compatible with your connectors.

6. Keep it simple — pick the safest system fit for the job, not the fanciest.

Final Word from Dr Scaffold Energy absorbing lanyards save lives — but only when they have the space to do their job. Four metres clearance is a good working rule. Under that? Switch to equipment that completely stops you from falling in the first place.