Demolition News has celebrated its first week with the launchof its first ever vieo podcast, an interview with Richard Comley of CG Comley & Sons Ltd on the subject of Contaminated Concrete. We look forward to receiving viewers comments.
Nobody wants to see a school demolished, least of all in ht eUK where the education system is in disarray. But you would have thought that someone might have raised the alarm when the excavators and mobile plant arrived on this site, wouldn’t you?
Letsrecycle.com has carried an article on an interesting diversification by UK demolition contractor 777, the company perhaps best-known as the owner of one of the UK’s largest high-reach excavators.
Details of their recent diversification can be seen here: http://tinyurl.com/6fgwmj
Midlands-based Coleman & Co. has taken delivery of a new Kocurek-modified Liebherr machine that boasts an upward reach of over 65 metre, making it arguably the UK’s largest. A full report on the new machine will appear in the September issue of Demolition & Disamntling but here’s a photo that shows just how big the machine really is.
Komatsu claims that its Dash-8 excavator operator’s cab is its strongest yet. Having seen this video, it would be difficult to argue with that.
In November last year, an issue that many building materials manufacturers have been forecasting for years finally reached the public consciousness. A factory in Scotland, built in the 1990s, was being demolished until the Scottish Environment Protection Agency (SEPA) intervened to halt the work. SEPA had the full weight of the law behind them due to the environmental threat from the building’s commonly-used foam insulated sandwich panels.
The repercussions from this one intervention have rippled through the UK’s commercial building industry, as funders, owners, manufacturers, specifiers and demolition contractors are realising that, at the end of many buildings’ lives, massive and expensive clean-up operations are inevitable. And the question, which has yet to have a definitive answer, is: who foots the bill?
Demolition was halted at the building, the former Chunghwa television factory in Mossend, Lanarkshire; because the foam material is officially designated as hazardous waste, due to the presence of blowing agents that contain ODP (Ozone Depletant Potential) and pose a potential pollution threat to the water table. The CFCs and HCFCs used for blowing the foam are similarly harmful to the environment as the propellants in aerosols which caused such a media storm until they were banned in 1989 and 1994 respectively.
SEPA found that demolition contractors were stripping panels from the building, crushing them and sending them to landfill, releasing the harmful substances.
Today the most popular method of disposing of foam-filled sandwich panels is to crush them or burn off the foam to recover the steel. But this runs counter to EC Regulation 2037/2000, which states that, due to their make-up, these insulation panels must in fact be recycled in exactly the same way as refrigerators, and cannot be cut, crushed or disposed of by any other means. And this is where the big bills lurk.
The process is complicated and expensive. First, the panels must be removed carefully from the building without being bent, torn, cut or broken – any damage at this stage would release the harmful substances and they need to be delivered flat in order to go through the correct disposal process.
Next, somebody has to pay for their delivery transport to the fridge recycling plant, of which to date there are an extremely limited number in the UK so the distance involved may be long and the transport costs high. When delivered, the panels must be cut to a suitable size. Panels are usually several metres long but must be reduced to no more than 2.0 x 1.0 metres for the process, and of course the cutting must be done in an isolated room to capture the dangerous substances released. Only once cut can the panels be fed into the recycling process.
Based on this process, a conservative estimate for the clean-up cost would be £13 per square metre (although costs in excess of £30 have been mooted); and when multiplied by the quantities of foam that hides in the roofs and walls of buildings nationwide, it runs into the billions.
Between 1992 and 2004 (at which point the ODP substances were outlawed), the manufacturers’ own figures suggest that some 83.5 million square metres of this same product were specified in the UK alone. In fact, this material had also been in use since the early 80s so the total figure will be much higher. And specifiers must not think that ODP-free material made since 2004 is exempt: in 25 years or so, when an average industrial building reaches the end of its life, there will be no visible way of knowing whether or not the foam insulation is pre- or post- 2004. The 2005 Montreal Protocol, therefore, advised governments globally that it will have to be recycled in exactly the same way. To complicate things further, post-2004 panels are often blown with Pentane, which is potentially explosive and must therefore be processed in a specially isolated area with a nitrous oxide atmosphere.
The industry as a whole is now facing high environmental and financial costs associated with the disposability of these panels, at a much earlier than expected time. The implications of this are that correct disposal methods may be ignored, either due to a lack of knowledge and information, or in some cases in favour of cheaper but unlawful and potentially damaging solutions. These, of course, will simply create a much more serious, costly, damaging and dangerous problem.
I do not believe that the specifiers who chose these products, or the demolition contractors who were halted by SEPA, are to blame. Insufficient information has been provided to the market regarding the ecological legacy that these products were to leave behind, and it is the manufacturers who must do the decent thing and foot the bill.
Further information can be found at the following links:
The NFDC 2008 Convention in Palma, Majorca marked the official launch of the Federation’s new guidance on the deconstruction of high rise structures. As with the Federation’s crusher guidance, my involvement in the production of the publication prevents me from giving an impartial review but the following article does give an insight into the content.
Copies are available from the National Federation of Demolition Contractors (www.demolition-nfdc.com)
Back in 1991, Allied Forces were embroiled in the Gulf War against Saddam Hussein in Iraq, there was a President Bush in the White House, and in Staines, the finishing touches had just been put to a set of guidance notes on the deconstruction of tower blocks.
Seventeen years later, Saddam may be gone but US and UK forces are still in Iraq; there’s another Bush in the White House; and the new edition of the NFDC’s Guidance on the Deconstruction of High Rise Structures has just been completed.
Two Decades of Change
Yet while things seemingly remain unchanged in US politics and international policy, the new set of guidance notes is a markedly different animal. “It is a testament to the original document that it was still in daily use 17 years after it was written,” says co-author of the new edition John Woodward. “But when we looked at it, it really polarised just how much our industry had changed in the past two decades.”
For one thing, the previous document made regular references to both high-balling and explosive techniques. “Obviously, explosive techniques are still utilised and have become far more specialised over the interceding years and their use is largely restricted to specific applications so we decided that it would be best to look at those in a separate guidance,” Woodward continues. “In addition, while high-balling was a highly productive and efficient demolition method, it has been largely consigned to the industry history books. So we have focused primarily upon floor-by-floor or ‘top-down’ methods this time around.”
The resulting document – produced by an NFDC working committee involving Woodward, NFDC CEO Howard Button, Tilley & Barrett’s Paul Brown and Demolition & Dismantling editor Mark Anthony – is the Federation’s most ambitious and comprehensive set of guidance notes to date.
Safe Working Practices
“The process of floor-by-floor deconstruction is a complex one and, as we were determined to define safe working practices and acceptable levels of control for all stages of the process, we knew from the outset that this publication would be a massive undertaking,” Woodward explains. “Even the scope of the guidance which we finally set at structures of 18 metres and above, was the source of a great deal of discussion because, once again, the goalposts have moved somewhat since the previous edition was published.”
Woodward cites legislation like BS6187:2000, Control of Asbestos Regulations 2006 and the Construction (Design & Management) Regulations 2007, all of which were introduced after the original guidance was published, and which had to be taken into account in the writing of the new one. “Legislation is constantly changing but we cannot just ignore it or offer guidance that is isolated from current regulations,” Woodward asserts. “So the new guidance makes constant reference to the very latest legislation and offers specific advice that anyone using the guidance should also produce a method statement and risk assessment and take into account prevailing site, environmental and regulatory conditions.”
In some ways, the degree to which legislation, planning and control are covered further highlights the way in which the industry has developed in the past two decades. Before the guidance makes any specific recommendations on demolition and deconstruction methods, the co-authors spent five pages covering subjects including roles and responsibilities; safety legislation, management procedures; and project planning and notifications.
“Today’s demolition contractor must abide by a huge and growing number of rules and regulations before they even set foot onto a site,” Woodward explains. “As one of the primary aims of the new guidance was safety, it was vital that we took all of this into account. But it did highlight just how heavily regulated this industry has become.”
Scaffold & Protection
Another key element of the new guidance is the subject of scaffolding and protection, a vital consideration in almost all floor-by-floor deconstruction projects. The new publication recommends that all scaffold should be designed by competent and qualified scaffold designers who will provide scaffold drawings and calculations. It further recommends that the design incorporates suitable and sufficient ties back to the main structure in accordance with BS5973.
“Experience has shown that for demolition scaffold, more scaffold ties than recommended in BS5973 should be provided to ensure that the scaffold will always have sufficient ties as the scaffold is dismantled with the demolition,” Woodward explains.
Woodward says that the new guidance will be previewed at the 2008 NFDC Convention in Palma, Majorca with the full launch to NFDC members following immediately afterwards. “It is two years since the NFDC’s guidance on the use of high reach excavators was introduced. That publication has been distributed across the US and Europe, has been translated into French and has recently been reprinted for the second time,” Woodward says. “Given the universal use of floor-by-floor techniques, we expect a similar level of demand for the new guidance.”
Although the new guidance is likely to achieve international recognition, Woodward says that it is aimed primarily at helping NFDC members in their day to day business, and that the publication was produced with the assistance of members across the UK. “This new set of guidance notes is a perfect example of the National Federation of Demolition Contractors working with and for its members,” Woodward concludes. “During the research of this guidance, the working committee spoke to members in all five regions of the Federation to gain their expert opinion and input. And the production of the guidance has been partially sponsored by associate members JCB and Sandvik Mining and Construction,” Woodward concludes. “The result is a guidance of which the Federation can be rightly proud and which will be of daily help to member companies and their employees.”
In response to the concerns shown by the UK’s Health & Safety Executive, the National Federation of Demolition Contractors has produced a new set of guidance notes on the safe use of mobile crushers in a demolition environment.
As one of the co-authors of this work, I cannot be expected to give an unbiased rewiew of the publication. However, the following article does give an indication of the content.
Copies of the new guidance are available from the NFDC (www.demolition-nfdc.com)
Like the demolition and recycling sectors, the quarrying and mining sector utilises track-mounted jaw and impact crushers. Both use these highly specialised machines for materials reduction and processing purposes. And both industry areas require men to interact with these machines on a continuous basis. But that, largely, is where the similarities end. While most demolition sites are transient and short-term, mines and quarries remain fixed for prolonged periods of time, allowing mine and quarry operators to set in place measures to protect their workforce from falling into the crusher chamber or from being struck by material ejected by the crusher. Mines and quarries are usually large, open areas unencumbered by obstacles, unlike demolition sites where space is often at a premium. And the quarrying sector has experienced fatalities from the incorrect use of mobile crushing equipment while, thankfully, the demolition industry has been rather more fortunate.
Against this background, the National Federation of Demolition Contractors was quick to react when the Health and Safety Executive issued its own guidance notes on the safe use of mobile crushers. “As with any item of legislation designed to improve the safety of our workers, we welcomed the HSE’s initial guidance notes and we generally supported them when they implemented the rules and served some demolition sites with prohibition notices when they found operatives on the crushers while they were working,” says NFDC chief executive Howard Button. “But we were also extremely conscious that the HSE guidance had been written largely in response to injuries and fatalities in quarry applications and that some of their recommendations would prove difficult or impossible to adhere to within a demolition environment. That is when we decided to produce our own demolition-specific version.”
To assist in the process of producing the new guidance notes, the NFDC enlisted the help of Federation associate member Sandvik Mining and Construction, a recognised leader in the field of mobile crushing and screening equipment and the owner of both Extec Screens and Crushers and Fintec Crushing and Screening. “We used the HSE guidance as our starting point but we knew that the machines and the way they’re used differs somewhat in the demolition and recycling sector so we wanted the input of a company with a foot in both camps,” Button continues. “A surprisingly large number of NFDC corporate members currently run Extec and Fintec machines so Sandvik seemed to be the most sensible company to partner us.”
The resulting document is a punchy, quick reference that addresses all the key issues of safety surrounding these highly productive and yet potentially hazardous machines. “In the right hands, a mobile jaw or impact crusher is a highly productive piece of equipment that is every bit as common in the demolition arena as a high reach excavator,” says Sandvik’s global product line director John Nethery. “But without proper planning or training, these machines do have the ability to cause injury. As a leading supplier of this equipment, we were delighted to have been invited to participate in helping address these important safety issues.”
The new guidance notes, which will be issued to NFDC members immediately after the NFDC 2008 Convention in Majorca at the end of August, identifies and addresses all the key risk areas including machine guarding, clearing blockages, slips and trips, and the interaction with the loading machine. The guidance also addresses the most contentious of all the original HSE guidance; the presence of a person on the crusher’s operating platform while the machine is working. “The recommendations in the new NFDC guidance makes it very clear,” Nethery continues. “A properly designed mobile crushing operation should not need any person to be present on the crusher access platform during normal crushing operations.”
Multitude of Risks
Nethery asserts that any person on the platform during operation faces a multitude of potential risks including being struck by objects ejected from the crusher; being pulled into the crushing chamber when attempting to pull out contaminants or oversize material; being struck by an excavator or wheel loader bucket; and exposure to noise, dust and vibration.
“One of the key areas of concern for us as a manufacturer of this equipment is the issue of Whole Body Vibration,” Nethery says. “Anyone working on a mobile crusher while it is in operation could be exposed to constant, low-frequency vibration that should be avoided.”
Nethery believes that the primary reason operatives have traditionally stood on the operating platform is to tackle blockages and bridging. But he further believes that this can be avoided through thorough pre-selection of materials and via the use of stand-alone and isolated picking stations to prevent blockages, and boom-mounted breaker booms to remove them when they occur.
“Demolition contractors are generally excellent at materials segregation, partly because they truly understand the value of the materials being recycled but also to protect their crushers from tramp metal and oversize material,” John Nethery concludes. “By ensuring that such vigilance is the norm and by following the advice of the new guidance notes, demolition contractors can remove the need to put a crusher operator in harm’s way altogether.”
Mobile crushers are now a common site on demolition sites the world over; and the C-12+ from Extec is currently the world’s best-selling model. This video gives an indication of why.
The new edition of Construction & Demolition Recycling is out now and makes for fascintaing reading, particularly the Myth Busters article on page 36