Fall Arrest Systems
FALL ARREST
When a work restraint system cannot be feasibly offered, a fall arrest system can then be considered. Fall arrest systems are designed to ‘limit the consequences of a fall should it occur’.
Lifeline system will arrest a users’ fall, only if the required fall clearance has been allowed.
Fall clearances must be factored in when a fall arrest system is designed, considering the following factors;
- Building height
- Free fall distance through fragile roof areas/roof lights/canopies etc
- Free fall distance from roof edges
- To the ground
- Lower level roofs/adjacent buildings
Although fall arrest systems are often employed to give a user full roof access, they come with major disadvantages, such as:
- They do not stop a fall from height occurring as the user has flexibility of PPE lengths.
- They can only be used on buildings with the required free fall clearance from all fall hazards including through roof lights.
- A full rescue plan must be in place to return the user to safety, often this is overlooked.
- The users must be trained so they can use extra PPE equipment safely including extended
Free-fall Clearances
Free fall clearances are often overlooked when a fall arrest system is designed.
It is imperative they are calculated using a calculation programme by the manufacturer, to prove that if a fall was to occur, the distances required for the system to effectively arrest the users fall can be assured.
System deflection and wire elongation is calculated using the Soter calculation package, taking into account system length, post spacing and maximum span length, and the number of users.
This calculation package is available to all recognised Soter installers. SFS can also make design calculations in house on request.
Once system deflection and wire elongation is known, this distance can be added to the following measurements to calculate a free fall clearance distance:
- Users Height (A)
- Lanyard Length (B)
- Deployed shock absorber length (C)
- Safety Factor (D)
= Minimum free fall clearance required (Z)
fall arrest system
Fall Arrest systems protect you after you fall: they stop the fall before you hit the surface.
These systems use a body holding device connected to a reliable anchor; they arrest and restrict a fall preventing you from colliding with the ground or structures, whilst limiting the forces on the body.
When should you use it?
When you are working near a fragile surface, narrow ledge or unusual building or roof shape and are using lanyards or a rope, there is a good chance you might fall off or into the building.
This is when you need a Fall Arrest system, together with personal protective equipment (PPE). You also need additional training and, by law, you are required to have a rescue plan in place. This means that you can be retrieved as soon as possible should you fall.
WE WILL PROVIDE THE BEST SOLUTION FOR YOUR REQUIREMENTS
Not sure what solution you need? Do you want to prevent people from reaching the edge of a roof/fall hazard, or do users need to work freely on a roof without any restrictions? Dash4safety team can help.
Our qualified engineers will complete a site survey or work to your drawings/specifications to determine the most appropriate solution for your roof type, user requirements and budget.
Fall arrest and fall restraint lifeline systems have been tested for use on most roof types and conform to current standards, including:
- BS EN 795 2012. BS8610:12017 BS7883:2019
