Fall Prevention Devices Working At Heights

Fall prevention devices are pieces of equipment designed to prevent falls for temporary work at heights, and once in place require no further adjustments by workers that use those devices. 

Temporary Work Platforms

Temporary work platforms are working platforms besides permanently installed fixed platforms that are used for providing a working area for the job’s duration. 

The platform’s design ensures that workers don’t fall. 

Temporary work platforms include building maintenance units, elevating work platforms, scaffolds, workboxes, mast climbers, mobile or portable fabricated platforms or any other platforms that provide a working area and are designed to include fall prevention mechanisms.

Scaffolding

Scaffolding can be a highly effective way to prevent falls, but under the WHS Regulations, there are specific requirements applying to some types of scaffolding.

A person that has control or management of a scaffold should not permit the use of a scaffold from which an object or person may fall more than 4 metres unless written confirmation provided by a competent person is completed. 

The person is also required to make sure that:

• A competent person inspects the scaffold as well as the supporting structure prior to use, after any incident likely to affect its stability, such as a severe storm, at least every 30 days, and after any repairs.
• Unauthorised access is not allowed on incomplete scaffolding that’s left unattended (for example, by attaching warning signs and danger tags at appropriate locations).

Scaffolding work platforms are usually rated as heavy-duty, medium, or light. The safety considerations include:

• Scaffolding that conforms to the AS/NZS 4576 scaffolding guidelines as well as the AS/NZS 1576 Scaffolding series.
• Only competent persons should erect, alter, and dismantle all scaffolding. A scaffold from which an object or person could fall more than 4 metres should only be erected, altered, and dismantled by or under a licensed scaffolder’s direct supervision.
• Prefabricated scaffolds are not mixed components and are of the same type unless the manufacturer has approved the mixing of components. 
• Safe access to and egressing from the scaffolding is provided
• Edge protection (toe boards, mid-rails, and handrails) is provided at each open edge of a work platform.

If work is performed from a scaffold, measures must be taken to make sure that relevant workers understand:

• The kinds of loads the scaffold is capable of taking safely.
• Not to make alterations to the scaffold (such as the removal of planks, guard rails, braces, toe boards, ties, and planks) that are not authorised.
• That working platforms must be kept clear of any obstructions and debris along their length
• That defective or incomplete scaffolds should never be accessed.

If mobile scaffolds are used to perform work, workers must receive proper training to make sure that the scaffold:

• Is kept clear of open floor edges, penetrations, and powerlines
• Always stays plumb and level
• Isn’t moved while anybody is on it
• Isn’t accessed until the castors have been locked to prevent movement
• Is only accessed using internal ladders

Light Duty Suspended Scaffold

Suspended scaffolds are those that incorporate a suspended platform capable of being lowered and raised when in use. 

The common types of suspended scaffolds include:

• Work cages that are small cradles supported only by suspension rope
• Double rope scaffolds that have cradles supported by 2 rows of suspension ropes
• Swing stages that have cradles that are supported by just 1 row of suspension ropes
• Specialised types of suspended scaffolding typically used in lift construction before the installation of actual lifts known as false cars

Swing stages have several specific safety considerations, which include:

• Persons that service or install a light-duty suspended stage are licensed for advanced scaffolding or advanced rigging
• Persons that operate light duty suspended stages have undergone training in safe operation
• The specifications and working load are in accordance with AS 1576.4 
• If the swing stage is suspended by 2 wire ropes to each winch, a restraint lanyard and safety harness is attached to the swing stage at a suitable anchor point

The Scaffolding Code of Practice provides further guidance on the safe design erection, as well as the use of scaffolding, which includes suspended scaffolding.

Elevating Work Platforms (EWPs)

Travel towers, boom lifts, cherry pickers, and scissor lifts are all Elevating Work Platforms. 

The two most common types of EWPs are internal combustion engine and battery-powered.

Some are designed exclusively for hard surfaces while others are designed for use in rough terrain.

Safety considerations include:

• Platforms are only used as working platforms as opposed to a means of entering and exiting the work area unless the conditions outlined in AS 2550.10 have been met
• Workers that operate the platform have received training and instruction in the safe operating procedures for the specific type and brand of equipment, along with the safe use of fall-prevention equipment as well as emergency rescue procedures
• The platforms are only used on a solid level surface unless designed for rough terrain
• The surface area is checked to ensure that there aren’t any obstructions or penetrations that may cause overturning of the platform or uncontrolled movement
• The instructions of the supplier or manufacturer are consulted for guidance on safe operation
• Workers are licensed when operating boom-type elevating work platforms whose boom length of 11 metres or more
• Persons working in boom lifts, travel towers, or cherry pickers wear safety harnesses that are properly anchored.

Mast Climbing Work Platforms

The mast climbing work platforms are essentially hoists that have a working platform used for raising materials and workers to a temporary working position. 

The platforms use a drive system that’s mounted on an extendable mast that might have to be tied to a building under the circumstances the manufacturer prescribes. 

Mast climbing work platforms can be set up in either multi-mast or single-mast configurations. 

They are generally less than ideal for use if a structure’s profile changes at various elevations (for instance, if balconies protrude from the building or a building’s upper floors ‘step’ back). 

Only a person holding an appropriate scaffolding or rigging license should carry out or directly supervise the erection and dismantling of mast climbing work platforms.

Workboxes

Workboxes are designed to be supported by a hoist, crane, forklift truck or other mechanical devices for providing an elevated work area for people working from the box. 

They comprise of platforms surrounded by edge protection mechanism and must be designed in accordance with AS 1418.17.

Other working platforms, such as a scaffold or elevated working platform should be used as an alternative to workboxes where reasonably practicable.

The safety considerations and requirements include:

• Workers don’t leave or enter the workbox when suspended except in case of an emergency
• Workers stay within the workbox when being suspended or lifted
• The workbox isn’t suspended above people
• The crane is fitted with the means to lower it safely in case of a failure of the power supply or an emergency
• The workbox is fitted with the proper anchorage that can withstand the fall forces as spelt out in AS/NZS 1891.4. Workers are required to be attached to the anchorage by means of a harness or lanyard unless the workbox is completely enclosed
• The workbox is attached securely to the crane and designed for the task. A competent person should check the lifting attachments, workbox, and records prior to use
• The operator stays at the controls of the cranes at all times
• The crane is fitted with a safety hook and lashed accordingly
• An effective way to communicate between the operator and the person in the workbox is provided
• The crane has both a “drive-down” and “drive-up” controls on the hoisting and luffing motions and the controls are used. Declutching that allows free fall is not allowed while the workbox is in use
• The crane is sufficiently stabilised at all times when the workbox is in use
• The crane is fitted with the means to lower it safely in case of a power supply failure or emergency.

Forklifts with a Workbox

A forklift that’s fitted with a workbox should be attached securely to the forklift carriage and designed and constructed by an engineer in accordance with AS 2359.

The safety considerations include:

• The safety gate is self-locking and stays closed when in the elevated position
• No other devices such as pallets or ladders are used to gain additional height
• People aren’t raised on the tyres of the forklift trucks or the pallet.

Building Maintenance Units

Building designers should take into account the methods by which repairs, maintenance, or cleaning will be undertaken on structures or buildings. 

A building maintenance unit is a suspended working platform that’s power-operated and fixed permanently to a structure or building. It is used for access to windows for cleaning or building maintenance.

The safety considerations include:

• The units are designed in accordance with AS 1418.13 and operated by competent persons in accordance with AS 2550.13
• The platform has numerous, safety harness anchorage points that are clearly designated and capable of withstanding forces that a fall of any individual located elsewhere on the platform cause.

Platforms That Trestle Ladders Support

Trestle ladder scaffolds are only suitable for use at heights greater than 2 metres when toe boards and guardrails have been incorporated to prevent materials and people from falling off the working platform. 

The system, which includes planks, should be assembled according to the specifications of the manufacturer with a complete set of compatible components.

Trestle ladder scaffolds sometimes include outriggers for increasing stability. 

Trestle ladder scaffolds are best suited to light-duty tasks like rendering and painting. Work should only be done between trestles. 

450mm should be the minimum width of the working platform. 

Trestle alternatives should be considered, such as light-duty aluminium mobile scaffolds, small scissor lifts, modular scaffolding, and boom arms.

Perimeter GuardRails

Guard rails can be an effective fall prevention mechanism:

• At the edges of pits, shafts, and other kinds of excavations
• Around openings in roof and floor structures
• On top of structures and plants where access is needed
• At the edges of walkways, mezzanine floors, ramps, stairways, and landings
• At the roof edges

Guard rails should include a top rail 0.9 to 1.1 metres above the working surface as well as toe board and mid-rail. 

Prior to using the guard rail system, it is important to check that it will be sufficient for the potential loads. 

The momentum of a falling person determines the load resistance that’s required. 

For instance, the momentum of a person falling from a pitched roof is likely to increase as the roof’s pitch (angle) increases.

Safety Mesh

The safety mesh is for preventing internal falls through a roof. 

A safety mesh that securely fixed should provide protection for people that install roofs and provides long-term protection against falls for repair and maintenance workers. 

Safety mesh doesn’t prevent falls from roof edges or through holes in roofs, which is why it should always be used together with appropriate edge protection, fall arrest systems, or guard rails. 

Safety mesh should be in compliance with AS/NZS 4389 that specifies the minimum requirements for the design, installation, testing, and construction or safety mesh to be used in industrial and commercial building applications. 

The safety mesh should be made from 2mm diameter wire with a tensile strength of at least 450 MPa and welded into a mesh where the longitudinal wires are 150 mm apart at most and the cross wires 300 mm apart at most. 

It should be installed according to the instructions from the manufacturer and by a competent person, who should be protected against the risk of falling through the use of proper control measures such as fall-arrest systems, elevating work platforms, or scaffolding.

Special care is needed to make sure that the safety mesh is connected securely to the structure and that the overlap between adjacent sections of the mesh is enough to generate the strength required to resist the force of a person that falls onto it. 

The safety mesh should also be covered by roof cladding once it is reasonably practicable after installation.

If you are looking for knowledgeable and experienced scaffolders, who have leading-hands that work together with you and offer expert advice, please contact us at Skelscaff today on 1300 266 607 or email us at contact@skelscaff.com.au.