IAN FRYER AT RMD KWIKFORM EXPLAINS HOW THE LATEST SAFETY SCREEN SOLUTIONS HAVE OVERCOME SOME OF THE OBSTACLES AND CHALLENGES FACED BY TRADITIONAL
EDGE PROTECTION PRODUCTS
Increasing urbanisation has led to a growth in the construction of high-rise and other tall buildings around the world. While the skylines of some of Ireland’s biggest cities do not yet match others around the world in terms of height, this is looking more and more likely to change in the future, with high-rise developments viewed by many key figures as a way of solving the country’s housing demands for the coming years. As such, debris protection for those involved in these developments should be a key concern. What, then, are the key considerations that contractors need to bear in mind when selecting a suitable edge protection system, to ensure contractors and their employees, as well as the general public, stay safe and secure?
High-rise construction is an accepted global model for managing the increasing number of city dwellers, as more than one million people around the world move to cities every single week. The global trend for high-rise construction looks set to be reflected in Ireland’s cities more and more over the coming years too. Only recently, the chief executive of the Bank of Ireland urged the next government to urgently examine how it can deliver higher density and higher rise development as smoothly, quickly and efficiently as possible. Ireland’s population is set to grow by one million in the coming decades, with demand for new housing climbing over 500,000 units by 2040. However, last year only 21,000 new homes were delivered. Following the guidelines that have been published under Ireland’s National Planning Framework which remove the height limits set by local authorities within their respective development plans, the strategy of building residential developments ‘up’ – coupled with sound urban design and strong transport links – is seen as a key means of meeting the housing demands that Ireland will face in the future.
Health and safety should never be compromised in the construction industry. Nevertheless, contractors are under incredible pressure to turn developments around quickly, on time and on budget. When considering the sheer scale of a project, tight timeframes and the number of sub-contractors and teams all working under this kind of pressure, it’s esay to see how potential safety risks can arise.
The role that multi-level safety screens play in helping to drive productivity and prevent accidents could be clearly seen in the study. A total of 49% agreed that they offer productivity gains, while also improving health and safety while 35%, the second highest ranked finding, said these systems also help speed up working cycles on facades.
Considering the wider context of increasing urbanisation, the anticipated growth in high-rise and tall building construction in Ireland and this research, debris protection to help ensure the health and safety of workers and the public has never been more important. This is particularly true with cast concrete construction, where slabs extend beyond a building’s footprint and the opportunity for debris to fall over the edge is high.
The potential impact of falling debris should not be underestimated. For example, an M20 nut falling 12 floors gains 50 joules of kinetic energy, and more than 14 joules is enough to fracture a human skull. In inner-city areas with limited space, pedestrian walkways on the periphery of a site need to be protected from falling objects and then workers on the ground – who might be transporting goods from one point to another – must be kept safe from the building work that is taking place above them. On the other end of the spectrum, falls from height are the main cause of fatal accidents for those working in the construction industry in the EU, for example. And then there’s the issue of ensuring neighbouring buildings are not damaged or a contractor could be faced with a costly penalty and dispute. In short, the construction industry has a duty to make the protection of people an absolute priority. For those seeking an assured debris protection solution, safety screens are a best practice approach for managing health and safety.
Providing maximum debris sealing, a safety screen system delivers assured perimeter edge protection for site operatives, preventing falls from height, as well as sealing in construction debris and stopping objects from falling. Safety screen systems also accommodate various climates, with solutions available that can shelter workers from wind and rain, while providing ventilation too. This, ultimately, helps minimise downtime as well.
Other benefits include helping reduce vertigo for workers, further improving productivity levels too. Multi-level safety screens can, therefore, significantly speed up working cycles for contractors.
There are a range of key considerations that contractors need to bear in mind when specifying a safety screen system. The available space will influence whether safety screens arrive preassembled or are assembled on site. The capabilities of on-site operatives may also dictate whether systems arrive ready-assembled.
Wind load is also an important consideration when erecting safety screens for tall buildings and only becomes more critical as the height increases. Location is also a key consideration when specifying safety screens, as these can represent a significant opportunity to carry publicity messages for a development. Using this opportunity to help offset the cost of the system can enable the contractor to justify the use of safety screens on factors other than just perimeter protection.
OVERCOMING TRADITIONAL OBSTACLES
Many of the latest safety screen solutions have been designed and developed to address the challenges associated with previous systems. In the past, screens could often not be lifted until the concrete slab had cured and the falsework had been struck. The screens would often not be big enough to cover two storeys, meaning column construction would stop just over one storey above the last cured level. This meant that column construction would have to be carried out above the protection of a screen or workers had to wait until the screen could be lifted.
In contrast, many of today’s systems can be removed and lifted while the slab shoring is still in place. A lot of systems now also span two full storeys above the wet deck level, which enables work to be carried out on multiple levels at any one time. This ensures the slab above can also be cast, as well as the columns above. The safety screens can then be lifted up, with typically at least a metre of protection available. Both of these measures can help save critical time for contractors.
In the past, steel mesh was typically the only screen cladding option available. While this is effective, it does have its limitations too. Nowadays, safety screens come with a variety of cladding options, allowing the contractor to select the best one for the job. Steel mesh provides a fully rentable cladding option for where multi-use is required. Alternatively, plastic film cladding also offers a number of advantages, such as protection from the elements, particularly the wind. This option also offers contractors advertising opportunities, as branding and marketing messages can be printed onto it while it is on site. Fire retardant nylon mesh screens also offer a very cost-effective alternative.
Another common problem in the past was that screens would often struggle to close corners or would not be well sealed between modules. There were also many instances where the gap between the lower slabs and the screen would not be sealed properly. Many older safety screens could not be relied upon to provide sufficient edge protection, which meant independent systems had to be specified, adding to costs.
Today’s safety screen systems benefit from features such as rotating cladding beam ends and compression edge seals to help eliminate gaps. To seal lower slabs and the screen, plastic cladding flaps and rotating ply seals can help and modern solutions are designed with perimeter edge protection as a top priority too, negating the need for additional systems. Ultimately, contractors need to make sure that they have every confidence in the safety screens selected to help with debris protection. By taking a best practice approach when selecting an appropriate solution and taking advantage of the latest edge protection systems available, Irish contractors can make sure on-site perimeter protection is assured.
Ian Fryer is Divisional Product Innovation Manager at RMD Kwikform
Editor of Irish Construction Industry Magazine