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Safety On The Edge

Published: 04th Jul 2013 in OSA Magazine

Whether you’re using personal or group controls, Francois Barton gives you an insight into height safety in New Zealand.

Investigations by the New Zealand Ministry of Business, Innovation and Employment into falls while working at height show that more than half of these falls are from fewer than three metres, and most are from ladders and roofs.The cost is estimated to be $24 million a year – to say nothing of the human cost.

Factors contributing to these injuries include:

• A lack of or inadequate planning and hazard assessment
• Inadequate supervision
• Insufficient training for the task being carried out
• Incorrect protection or equipment choices
• Incorrect use or setup of equipment, including personal protective equipment (PPE)
• An unwillingness to change the way a task is carried out when a safer alternative is identified
• Suitable equipment unavailable

More injuries happen on residential building sites than in any other workplace in the construction sector.

The project

To address the issue of workplace falls from height, in 2012 the Ministry initiated a targeted harm reduction programme, the Preventing Falls from Height Project.

The project was a result of the New Zealand government’s Construction Sector Action Plan, which was put together by the Ministry of Business, Innovation and Employment, the Accident Compensation Corporation (ACC) and the Construction Safety Council.

The project focuses on raising awareness of the problem, and providing safety information on how to manage this significant hazard. Enforcement was targeted in areas where there was a risk of corners being cut, to ensure businesses took their ethical, social and legal responsibilities seriously.

The first step of the project was to produce the Best Practice Guidelines for Working at Height in New Zealand.The guidelines were developed by the Ministry in association with 21 businesses and industry associations from across New Zealand’s construction sector.

The guidelines are a critical element of the programme as they give all involved with working at height clear direction on how to manage their work – in a way that will bring down the death and injury toll.

The guidelines outline how people working at height and those involved in the process can meet their legal obligations through the Health and Safety in Employment (HSE) Act and the Health and Safety in Employment Regulations, 1995.

New Zealand’s HSE Act, 1992, sets out the performance required of duty holders. People with a duty must, where practicable, ensure the safety of workers when they are exposed to a fall or where the hazard of a fall exists.

The guidelines outline best practise methods for assessing work at height hazards and the control methods for preventing falls, and apply these to all the people who have a legal obligation to provide a safe place of work and ensure safe work practise.

The guidelines provide a generic guide that is not industry specific. Many industries have their own guidelines that address specific issues, which are unique to their working environments, such as the electricity sector.


A hazard assessment must be carried out for all work at height. It is essential that the hazards are identified before the work starts and that the necessary equipment, appropriate precautions and systems of work are provided and implemented. Too many falls from height are caused by a failure to plan and organise work properly.

Planning a safe approach to working at height means:

• Identifying hazards
• Assessing hazards
• Controlling hazards
• Monitoring your approach
• Documenting your approach

Hazards must be identified anywhere someone working at height could fall. Four ways of identifying hazards are:

1. Physical inspections – Walk around the workplace using a checklist to identify and manage hazards.
2. Task analysis – Identify the hazards involved in each task of the job.
3. Process analysis – Identify hazards at each stage of the production or service delivery process.
4. Analysis of accident investigation – Identify hazards and causal factors from investigations involving similar types of work.

Identified hazards must then be assessed to decide if they are significant, how badly harmed someone would be if they fell, and how likely a fall could be. If serious harm could result, then it’s a significant hazard.

Once a significant hazard has been identified and assessed, specific steps must be put in place to control the risk of this hazard and keep people safe.

Hierarchy of controls

Where the potential for a fall exists, the following hierarchy of controls must be considered by duty holders.

Can the job be done without exposing people to the hazard? This can often be achieved at the design, construction planning and tendering stages.

If elimination is not practicable, steps can be taken to isolate people from the hazard.This can be achieved using safe working platforms, guardrail systems, edge protection, scaffolding, elevated work platforms, mobile scaffolds, and barriers to restrict access.

If neither elimination nor isolation are practicable, what steps can be taken to minimise the likelihood of any harm resulting? This means considering the use of work positioning systems or travel restraint systems, safety harnesses, industrial rope access systems and soft landing systems.

Minimisation is only acceptable when the options of eliminating and isolating the hazard have been exhausted. Doing nothing is not an option.

Selecting the right equipment

To select the best equipment for keeping people safe at height, workers must start with the most effective control – elimination – and then work through isolation and minimisation.

As each control is assessed, the duty holder should be thinking about:

Working conditions – Slopes, poor ground quality, obstructions and traffic can determine the choice of work equipment. A mobile elevating work platform (MEWP), for example, can reach across bad ground or obstructions as long as its stability is not compromised. A MEWP may be preferable to a tower scaffold in such circumstances

Distance to be negotiated for access and egress – Ladders are likely to be less suitable for higher access

Distance and consequences of a fall – A fall arrest lanyard would be ineffective if the deployment length was greater than the fall height, because the user would hit the floor before the system could deploy

Duration and frequency of use – Long duration, higher frequency work justifies a higher standard of fall protection, such as a tower scaffold rather than a ladder. A ladder, however, may be justified for short duration, low risk work

Evacuation and rescue – If evacuation from a deployed fall arrest system would be difficult, choose other work equipment, such as a MEWP

Additional risk posed by the installation and removal of work equipment – A MEWP used by one person may be less risky than two or three people erecting a tower or scaffold for one person to work safely

Once the right equipment has been selected, it’s critical it is used and maintained properly. Poorly maintained equipment or the wrong equipment can be just as dangerous as having no equipment at all.


As well as the hierarchy of controls, workers must think about the controls that prevent more than one person from falling. These are group controls.

The best work methods are those that don’t require any active judgement by the workers to keep themselves safe, such as edge protection, scaffold, and elevating work platforms.

Personal controls only look after individuals and rely on active judgement by the user for them to work safely; for example, total restraint and fall arrest systems.Training, inspection and equipment maintenance are critical for these personal control measures to be effective.

Group controls

Edge protection
Edge protection is used to prevent people, tools and materials from falling around the perimeters of a work area and openings, and where brittle material cannot safely support the weight of a person.

Edge protection comes in different forms:

• Proprietary systems that are bought ‘off the shelf’
• Scaffolding that supports a temporary edge protection system
• Timber that forms a guardrail and/or physical barrier

Edge protection is the preferred control for preventing falls from roofs on single storey buildings because it isolates multiple workers from the risk of a fall.

Where the hazard of working at height cannot be eliminated, some form of edge protection should be used to isolate workers from a fall. This includes single storey buildings and structures.

If this is not practicable then the use of scaffolding, MEWPs or temporary work platforms is a more acceptable alternative.

The use of edge protection requires forward thinking, as sourcing and erecting edge protection may take time. It should be installed as early as possible so that multiple groups of contractors, subcontractors and workers can use it throughout the project.

Edge protection should be erected, used and maintained according to the manufacturer’s instructions or design specifications. It should also be fitted with a top rail, mid rail and toe board or bottom rail.

In New Zealand, the design and construction of guardrails for sloping surfaces is governed by the Australian and New Zealand standard (AS/NZS) 4994 for temporary roof edge protection for housing and residential buildings.

Edge protection should be inspected regularly, especially after a storm or other occurrence that could affect its ability to prevent falls.

Timber edge protection
Temporary timber guardrails are sometimes used for edge protection. Timber edge protection must be constructed by a competent person and extreme caution is required to ensure the materials used are appropriate. Construction must take into account the forces that are likely to be applied to the edge protection as a result of the work undertaken.

Temporary work platforms
Temporary work platforms (TWPs) provide a place to work when working at height and are most often used for work carried out fewer than five metres above the ground level. Scaffolding more than five metres high must be reported to the Ministry of Business, Innovation and Employment because it must be erected by a person holding a certificate of competency.

There is a range of temporary work platforms:

• Scaffolding
• Trestles,podium,foldingandstep up platforms
• Constructed temporary work platforms
• Step platforms

TWPs with guardrails are preferred for working at height as they isolate workers from the risk of falling.Workers must be trained and have suitable experience with the types of TWPs being used.

Scaffolding is the most common type of TWP for working at height. It must have guardrails, including mid rails and toe boards, on the exposed sides and at the end of all working platforms, regardless of height.

Scaffolding needs to be erected, altered and dismantled by trained workers with suitable experience.

Trestle scaffolds
Trestle scaffolds are only suitable for low level work, such as light duty activities including plastering, painting, general fit out, and finishing. They should only be used when scaffolds or elevating work platforms cannot be used.

Trestle scaffolds should have a guardrail system in accordance with the manufacturer’s instructions. They should only be used without a guardrail system when the likelihood of a person falling and injuring themselves is low, such as short duration and low level work.

Trestle scaffolds that use scaffold boards or staging must be manufactured and used in accordance with the Portable Ladders Standards, AS/NZS 1892. Self-supporting trestle scaffolds, including horizontal structures designed to support one end of a light duty work platform, must be designed and constructed to comply with AS/NZS 1576.5 or other accepted international standards.

Podium, folding and step up platforms
These platforms are intended for short term, low level and interior work. If they are used outside on soft ground, sole boards are required to keep the platform stable.

Podium, folding and step up platforms should be used with a guardrail system in accordance with the manufacturer’s instructions.They should only be used without a guardrail system when the likelihood of a person falling and injuring themselves is low, such as in short duration work and low level work.

Step platforms
A step platform provides a safer alternative to a stepladder because it is more stable and provides a much larger work surface. A step platform should be used in preference to a stepladder, especially where the task involves working at height for extended periods, or with restricted vision; for example, when welding or carrying out other hot work.

Constructed temporary work platforms
A temporary work platform should only be constructed where there is no alternative work platform available. The platform’s construction must be supervised by, or otherwise carried out by, competent and skilled tradesmen, and suitable material must be used.

The platform should also have guardrails, toe boards and mid rails, and be able to safely support workers and materials necessary to complete the work.

The minimum width of a working platform is 675 millimetres and there must be unobstructed access of 450 millimetres.

Soft landing systems
Soft landing systems are erected on site to minimise the effect of a fall from height during construction, by providing an energy absorbing landing area. Most systems are designed for use inside a building where they are enclosed by walls or partitions.

Safety nets
Safety nets are used on construction sites and in similar locations, mainly to break a person’s fall and sometimes to catch or contain debris.

It is essential that safety nets are subject to regular examinations by a competent person and that they are periodically tested in accordance with the manufacturer’s instructions. These instructions should also be followed for installation, use and storage.

Personal controls

Total restraint systems
A total restraint system is a full body harness that is connected by an energy absorbing lanyard to a suitable anchorage point or horizontal lifeline. The system is set up to keep the worker from reaching the edge.

A total restraint system is the preferred control for preventing falls from roofs on single storey buildings when edge protection is not practical.

The system must be installed and used by, or have its installation and use directly supervised by, a trained and competent person.

A competent person must install a temporary roof anchor that is used as an anchorage for a total restraint system in accordance with the manufacturer’s or designer’s instructions.

The roof or other building component to which an anchor is attached must be checked by a competent person to verify that it is suitable for supporting the anchor.

A total restraint system is different to a fall arrest system because it isolates the worker from the fall by keeping them away from the edge. However, a total restraint system is capable of going into fall arrest. For this reason, workers must not work alone when using a total restraint system. Another person must be available to assist in emergency situations. Workers using total restraint or fall arrest systems must also have an emergency rescue plan.

Fall arrest systems
A fall arrest system is an assembly of interconnected components. Consisting of a harness connected to an anchorage point by a lanyard incorporating an energy absorber, it can be used where workers are required to carry out their work near an unprotected edge. Fall arrest systems do not prevent the fall; they minimise the impact of the fall by slowing and arresting a worker’s descent.

When fall arrest systems are used, workers must wear an appropriate safety helmet to protect them from possible head injury in the event of an uncontrolled fall.

Most fall arrest systems require a minimum distance to deploy, making them inappropriate for low level and single storey work. Other controls for managing the hazard of working at height should be assessed before deciding to use a fall arrest system.

Guideline enforcement

From July 2012, the Ministry began targeted enforcement to ensure firms were taking their ethical, social and legal responsibilities seriously, and making it their priority to prevent falls while working at height.

The Ministry was transparent about its enforcement expectations and published these on its website.To make it easy for construction companies to comply with the guidelines, a factsheet was produced which outlined what a duty holder could expect to happen if an inspector found height hazards were not being managed. For example, if an inspector observes inadequate or no precautions to prevent falls from or through a single storey roof and other structures, or unsafe use of ladders, a prohibition notice will be issued. If the problem can be rectified immediately, a written warning will be issued.

If an inspector finds evidence that the hazard of a fall from height has not been adequately managed, and appropriate steps and controls are not being taken, inspectors will issue an improvement notice.This may require the duty holder’s hazard management system to identify work involving the height hazard and the appropriate steps for carrying out the work safely.

Published: 04th Jul 2013 in OSA Magazine


Francois Barton

Francois Barton is the general manager (Southern Division) at the Ministry of Business, Innovation and Employment and the project sponsor for the Ministry’s Preventing Falls from Height harm reduction project.

The project

The Preventing Falls from Height project commenced in late 2011 and has included wide ranging stakeholder engagement, a media campaign, targeted enforcement by health and safety inspectors and the launch of the Best Practice Guidelines for Working at Height and for Working on Roofs.

By 2014 the project aims to significantly reduce work related injuries and fatalities in the construction sector resulting from a fall from height.

Extensive analysis of accident investigation files, interrogation of Accident Compensation Corporation data, and stakeholder engagement, highlighted that more than 50 percent of falls were from lower than three metres – many of which were falls from roofs and ladders.

This analysis identified builders, roofers, electrical workers, and painters and decorators as the most affected trades.The project team also identified that there was confusion about the requirements and options for working safely at lower levels.

Consequently, the project is focused on:

• Targeting residential construction with an explicit focus on single storey house construction
• Using proactive and targeted enforcement to level the playing field
• Promotingtheproject’sstrapline:‘Doing nothing is not an option’

Francois Barton


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