According to the HSE, falls from height remain the single biggest cause of workplace fatalities in Great Britain, accounting for around a third of all fatal injuries to workers each year.
Despite The Work at Height Regulations 2005 having been in force for two decades, fall protection isn’t always used. Sometimes, it is also the case that the wrong fall protection is chosen, meaning misunderstanding how each system works continues to put workers at unnecessary risk.
Two terms you will encounter regularly are fall arrest and fall restraint. They are often grouped together under the broader category of personal fall protection, and both involve a harness and an anchor point. But they work in fundamentally different ways, and selecting the wrong one for a given task can have serious consequences.
This guide from Metreel explains how each system works, the situations where each applies, and how UK regulations and British Standards should inform your decision.
Common Reasons For Workplace Falls
- Electric shock
- Impaired vision
- Lack of employee attention
- Lack of safety training/procedures
- Medical episodes
- Poor weather conditions
- Slippery surfaces
- Slow reflexes
- Tiredness
- Unexpected events
- Unstable structures
- Vertigo
Interactive learning platform O’Reilly, states that there are three basic causes of workplace accidents. These include chance occurrences, unsafe conditions, and employees’ unsafe acts.
While there may be measures as an employer you can put in place to reduce falls, the reality is that similar to any other workplace injury, it is not possible to fully eliminate every possible scenario from potentially occurring.
For example, in the case of medical episodes, the employee may have no prior history of such symptoms, making it impossible to predict, even if your business carries out regular health screening.
Instead, the focus should be on minimising the chances of injury if such an event were to occur, especially when all other possible safety risks have been eliminated as much as possible.
Businesses can do so by implementing both fall restraint systems and fall arrest systems. Here’s what you need to know about both to improve the safety of your workplace.
What Is a Fall Arrest System?
A fall arrest system does not prevent a fall. Instead, it stops a fall that is already in progress, limiting the distance the worker falls and preventing them from reaching the ground or a lower level.
The system typically consists of a full-body harness, a lanyard or self-retracting lifeline (SRL), and a reliable overhead anchor point. When a fall occurs, the harness tightens around the worker’s body to spread the load, and the lanyard or SRL arrests the descent within a defined free fall distance.
Fall arrest is considered a last resort under the hierarchy of controls. It should only be specified where fall restraint is not practicable.
Key characteristics of fall arrest:
- Stops a fall in progress rather than preventing one
- Requires a competent rescue plan before work begins (the worker cannot rescue themselves in most cases)
- Involves greater forces on both the worker and the anchor point during arrest
- Requires shock-absorbing lanyards or SRLs to limit arrest forces
- Worker may be at risk of suspension trauma while awaiting rescue
- Used where the worker must access areas close to or beyond a fall hazard
When to Use Fall Arrest
Fall arrest becomes necessary when fall restraint is not practicable. This typically includes:
- Work at or beyond the leading edge of a roof or elevated structure, where restraint would prevent the worker from completing the task
- Environments where the working geometry changes throughout the task, making a fixed-length restraint impractical
- Confined spaces or fragile surfaces where guardrails or collective protection cannot be installed
- Applications in the rail, steelwork or utilities sectors where movement across variable distances from edges is unavoidable
- Wind turbine maintenance, motorway gantry work and similar structures where overhead anchor points allow freedom of movement but restraint is not achievable
It is important to note that fall arrest must always be accompanied by a documented rescue plan. Once a fall has been arrested, the worker is suspended in their harness and cannot self-rescue in most situations. Suspension trauma, which a potentially fatal condition caused by restricted blood flow in a motionless, upright suspended worker, can develop within minutes. Pre-planning for prompt, safe retrieval is a legal requirement, not an optional addition.
What Is a Fall Restraint System?
A fall restraint system is designed to prevent a fall from happening in the first place. The worker is connected via a lanyard and full-body harness to a fixed or horizontal lifeline anchor point, and the length of the lanyard is set so that the worker physically cannot reach the fall hazard. Typically, the edge of a roof, platform or elevated structure.
Because the system prevents the worker from reaching the danger zone rather than catching them mid-fall, it sits higher in the hierarchy of controls under the Work at Height Regulations 2005. Restraint is the preferred option wherever it can be implemented.
Key characteristics of fall restraint:
- Prevents the worker from reaching a fall hazard
- Lanyard length is calculated to keep the worker safely away from the edge
- Does not require a rescue plan (though evacuation procedures must still be considered)
- Simpler to use and less likely to be used incorrectly than fall arrest
- Lower forces applied to the anchor point compared to arrest loads
- No shock absorber required in the lanyard
Both fall restraint and fall arrest systems must be designed and rated to BS 8437, the British Standard for selection, use and maintenance of personal fall protection systems for use in the workplace.
When to Use Fall Restraint
Fall restraint is the right choice when the worker can perform their task without ever needing to reach the fall hazard itself. Common scenarios include:
- Routine maintenance on flat roofs where the anchor point can be positioned to keep the worker well clear of the edge
- Working at a consistent, measurable distance from a hazard where lanyard length can be reliably calculated
- Tasks on racking systems, plant rooms or raised platforms where movement patterns are predictable
- Any environment where a fixed or horizontal lifeline can be rigged to physically prevent access to the danger zone
The key question is: can you guarantee, through the geometry of the system, that the worker cannot reach the edge? If the answer is yes, restraint is the appropriate choice.
If there is any doubt, such as because the working area is irregular, the task requires varying positions, or the worker could potentially trip and swing towards the hazard, the system must be treated as fall arrest rather than restraint.
What UK Regulations and Standards Say
The Work at Height Regulations 2005 establish a clear hierarchy that employers must follow:
- Avoid work at height where reasonably practicable
- Use work equipment or other measures to prevent falls (collective protection such as guardrails)
- Where falls cannot be prevented, use equipment to minimise the distance and consequence of a fall (personal fall protection)
Within personal fall protection, restraint sits above arrest in the hierarchy. The Regulations require that employers select the most appropriate option at the highest practicable level of this hierarchy.
BS 8437:2005 (updated 2010) sets the requirements for the selection, use and maintenance of personal fall protection systems used in the workplace. All fall restraint and fall arrest systems used in the UK must be designed, tested and rated to this standard. Equipment must also carry a CE or UKCA mark confirming conformity with the relevant PPE regulations.
Employers are also required under PUWER (Provision and Use of Work Equipment Regulations 1998) to ensure that work equipment, including fall protection systems, is suitable for its intended purpose, properly maintained, and used only by trained and competent personnel.
The Role of Hoop Structures and Cages
Fixed hoop structures and ladder cages remain a common sight on many buildings. However, research and incident data have shown that these can increase the risk of injury rather than reduce it, particularly in the event of a loss of consciousness, where the worker cannot grip the hoops and may be held in a suspended or contorted position. Modern fall protection guidance increasingly moves away from hoop structures in favour of properly specified fall arrest or restraint systems, which provide controlled protection regardless of the worker’s physical state.
Fall Arrest vs. Fall Restraint – The Bottom Line
Both fall restraint and fall arrest systems are often pitted against each other. The reality is while fall restraint is the preferred option as it involves stopping a fall before it takes place, it is not always feasible in all environments, especially where the flexibility of movement is required.
Compared with not putting in any measures at all, the consequences of a fall are far less likely to result in injury or death when either fall restraint or fall arrest systems have been put in place, and the correct training and maintenance has been carried out.
Fall Arrest Vs Fall Restraint FAQs
Do Both Systems Need To Be Designed To The Same Standard?
Yes. Both fall restraint and fall arrest systems must be rated to BS 8437. The distinction between them is in how they are rigged and used, not the construction standard.
What Are The Three Main Types Of Fall Arrest System?
The most common types are: lanyard systems with a shock absorber attached to a fixed anchor; self-retracting lifelines (SRLs), which allow freedom of movement and lock automatically in a fall; and horizontal lifeline systems, which allow the worker to traverse across a structure while remaining connected.
When Should A Fall Restraint Be Used?
When the nature of the work and the geometry of the anchor system can guarantee that the worker cannot reach the fall hazard. If there is any uncertainty, fall arrest must be assumed.
What Is Suspension Trauma?
Suspension trauma (also called harness hang syndrome) occurs when a worker is suspended motionless in a harness following a fall. Blood pools in the legs, reducing flow to the brain and vital organs. It can become fatal within 30 minutes. This is one of the primary reasons a rescue plan is mandatory with fall arrest systems.
What Is The Difference Between Personal Fall Arrest And Personal Fall Restraint?
Personal fall arrest stops a fall after it has begun; personal fall restraint prevents a fall from occurring. Both are personal fall protection systems (PFPS) under the Work at Height Regulations 2005, but they operate at different points in the hazard timeline.
Fall Protection Systems UK
Metreel offers specialist fall protection systems spanning various pieces of equipment and usage types. We’re based in Ilkeston, Derbyshire covering the UK and beyond.
If you would like to find out more about our fall protection systems, or if you’re interested in any other of the services we provide, please give us a call on 0115 932 7010, or drop us an email.
Alternatively, check out the Metreel Brochure to discover our full range of products and services.