Scaffolding rules and regulations
Three workers have suffered serious injuries after the collapse of scaffolding at a Milton Keynes construction site. But what safety rules and regulations govern the scaffolding industry?
The principal regulations are the Work At Height Regulations, which are, say the National Access and Scaffolding Confederation (NASC), "essentially criminal law".
The regulations, which are governed by the Health and Safety Executive (HSE), help to ensure that British and European standards for scaffolding are adhered to.
Experts say the British construction industry is one of the best regulated in terms of safety.
BBC correspondent Tom Symonds said health and safety laws in the UK had improved a great deal in recent years.
"For example, they're currently renovating Nelson's Column in Trafalgar Square," he said.
"Twenty years ago, when they did that, it was a matter of ropes and ladders whereas now it's a vast network of gates, scaffolding and poles.
"You almost have to build another building alongside the building you're working on to enable you to work safely.
"Health and safety laws have improved to that degree and that amount of scaffolding is now needed alongside a building."
Simon Hughes, scaffolding and work-at-height consultant to the NASC, said there were a number of things that could go wrong with a scaffolding construction which was why safety was taken so seriously within the industry.
"With a building of the scale of the one in Milton Keynes, you would expect to have a design engineer to do the design and then produce a set of drawings for scaffolders to follow," he told the BBC News website.
The engineer would have "the right experience and qualifications", usually to degree level in structural engineering.
The scaffolding structure would always be subjected to a handover inspection between the scaffolding contractor and the main building contractor.
"Once the scaffolding contractor's handed it over in good order, the contractor will take responsibility for it, making sure it's being used properly," he said.
Further inspections would then take place every seven days, he added.
During the weekly inspections, the contractor would be checking to make sure the scaffolding had "not deteriorated or been interfered with".
There were a number of common causes of scaffold collapse, Mr Hughes said.
"Wind plays a big part.
"The building it's tied to could fail causing a scaffold collapse or it could be a case of poor design or poor construction.
"And often we see instances of scaffolding overloading or the removing of ties because they're in the way of the building work. Or it could be a combination of these things."
Fortunately, cases like the one in Milton Keynes were "few and far between", he said.
But he said there would be lessons to be learned by all in the industry following "thorough investigations".
Construction lawyer Doug Masson - who saw the scaffolding collapse - said HSE investigations into the Milton Keynes incident may take some time.
"There will be a very through investigation by the authorities. One can expect this will be a site which nothing will be happening on until they are satisfied as to the cause."
But he also stressed the accident was a "pretty rare" occurrence.
"I've never, ever witnessed an accident like that and I've been on many, many sites," he told BBC News.
"Construction sites are dangerous place.
"That is why in this country we have such excellent control over safety issues on site."