CONTRACTORS and hirers are risking workers' lives by continuing to specify the wrong combination of fall arrest equipment, a leading safety specialist has warned.
The Health and Safety Executive has already issued a warning in March, telling employers not to use retractable fall arrestors or 'inertia blocks' over the edge of buildings because they risk shearing the cable or not arresting the fall.
This type of fall arrestor is intended only for vertical use, but has been used widely in construction for other applications.
But according to safety specialist Safesite, because of a general lack of awareness of the problems, the blocks are still being wrongly specified and are still in many hirers' fleets, despite safer alternatives now being available.
The firm has commissioned tests which have confirmed the risks of shearing and has written to all its customers to warn them of the dangers and to recommend an alternative, a shock absorbing rope grab.
Marketing director Graham Willmott said: 'A lot of hire companies are still offering inertia blocks, even though this problem was first raised nearly two years ago.
'Construction is a particularly harsh environment because of the exposed sharp edges and because it is not dealing with finished structures.'
Safesite's independent testing of a retractable lanyard with a 4 mm steel cable routed over the edge of a steel I-beam saw the cable shear completely when a 100 kg load was used.
When the webbing of the lanyard was routed over the beam instead of the steel cable, it failed to lock and thus also failed to arrest the fall.
Mr Willmott said the firm was recommending using a rope grab device as a restraint, together with its mobile man anchor, using 14 mm twisted rope. This would not shear in the same way, although he stressed that people needed to be trained to use it correctly.
He said: 'On the tests the rope grab showed no degradation because of the manner in which it runs across the exposed edge.
'We have recommended this to hire companies, but some have not showed much enthusiasm. Contractors need to be aware of the risks involved.'
The HSE is expected to make further announcements on the use of fall arrest equipment in the next couple of months, after researching the area.