Design of timber scaffold boards - TG20:08
- Thread starter Georgina Molloy
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woodexperts
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Broken Scaffold Boards - what can we do to minimise risk?
Unfortunately Gents IT IS NOT A ONE OFF. We at Woodexperts were being asked to give reports on around 5 or 6 broken boards per year, a figure that has now doubled in last couple of years.
The board you have included pictures of Toppers, contains large edge knots. They are well beyond the size allowed in the grading rules used to comply with BS 2482. The rate of growth is actually OK – the min allowable in the standard is 5 growth rings per 25mm ( 5 per inch).
Jakdan says boards are machine graded in response to GM’s question on safe loading capacities but Scaffold Connect is correct in saying that not all boards with bands on are graded and therefore not all safe – even when the industry FOOLISHLY calls these ungraded boards – “Grade A boards”!!
Please note well, unless the number of the Standard – BS 2482:2009 - is stamped on each band, then the board is not a “BS” board. It does not necessarily need to have a Kitemark, or some other third-party assurance mark on it: although that would be desirable. But unless it claims compliance with the British Standard and it has been graded by a competent person or a correctly-calibrated machine, then it should not be trusted and it should not be put onto a scaffolding, where someone's life may be at risk - not until it has been inspected and passed by a competent, properly-trained person.
HSE have picked up on this and are asking all contractors to ensure that if they have these “Grade A”(ungraded) boards in their system somewhere that they train their staff to cull out the ones which may fail in use due to them having strength reducing characteristics ( e.g. large knots or groups of knots, excessive slope of grain, excessive rate of growth).
Woodexperts are already working with board suppliers and contractors giving their staff practical training (not "calculation based") on how to recognise a safe scaffold board with short courses taking place on and off site.
Are reliable suppliers, who should already be aware of the risk involved with “Grade A” boards employing trained staff and is the company you work for doing all it can to keep inferior boards out of the system? Hopefully yes to both but we will be pleased to help wherever it is needed.
Here is a link to the "How Safe is your Board?" item that we wrote for NASC.
Scaffold Board Problems | TFT Woodexperts
Unfortunately Gents IT IS NOT A ONE OFF. We at Woodexperts were being asked to give reports on around 5 or 6 broken boards per year, a figure that has now doubled in last couple of years.
The board you have included pictures of Toppers, contains large edge knots. They are well beyond the size allowed in the grading rules used to comply with BS 2482. The rate of growth is actually OK – the min allowable in the standard is 5 growth rings per 25mm ( 5 per inch).
Jakdan says boards are machine graded in response to GM’s question on safe loading capacities but Scaffold Connect is correct in saying that not all boards with bands on are graded and therefore not all safe – even when the industry FOOLISHLY calls these ungraded boards – “Grade A boards”!!
Please note well, unless the number of the Standard – BS 2482:2009 - is stamped on each band, then the board is not a “BS” board. It does not necessarily need to have a Kitemark, or some other third-party assurance mark on it: although that would be desirable. But unless it claims compliance with the British Standard and it has been graded by a competent person or a correctly-calibrated machine, then it should not be trusted and it should not be put onto a scaffolding, where someone's life may be at risk - not until it has been inspected and passed by a competent, properly-trained person.
HSE have picked up on this and are asking all contractors to ensure that if they have these “Grade A”(ungraded) boards in their system somewhere that they train their staff to cull out the ones which may fail in use due to them having strength reducing characteristics ( e.g. large knots or groups of knots, excessive slope of grain, excessive rate of growth).
Woodexperts are already working with board suppliers and contractors giving their staff practical training (not "calculation based") on how to recognise a safe scaffold board with short courses taking place on and off site.
Are reliable suppliers, who should already be aware of the risk involved with “Grade A” boards employing trained staff and is the company you work for doing all it can to keep inferior boards out of the system? Hopefully yes to both but we will be pleased to help wherever it is needed.
Here is a link to the "How Safe is your Board?" item that we wrote for NASC.
Scaffold Board Problems | TFT Woodexperts
joebag
Well-known member
boards
could somebody give us some data on accidents/incidents directly attributed to failure of the working load on graded and ungraded scaffold boards,seems to be a lot of hse red herrings lately and won dering if this is something to consider or another nasc moneyspinner,thanks
could somebody give us some data on accidents/incidents directly attributed to failure of the working load on graded and ungraded scaffold boards,seems to be a lot of hse red herrings lately and won dering if this is something to consider or another nasc moneyspinner,thanks
woodexperts
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Sorry no data but what we can say is that over 95% of the boards that have come to us for inspection have been ungraded (Grade A) boards with excessive knots or excessive slope of grain. (One of the BS graded boards had failed because of rot due to bad storage - which is another area where staff can be helped ).
NB. Woodexperts are an independent company working to improve the use and reputation of timber and have no connections with organisations such as NASC. A lot of our work involves helping timber companies comply with regulation, especially the strength grading of timber in all areas of construction including roofing and scaffolding.
Wood is a natural material and has variable characteristics but it is good to know that all timber designs which involve strength graded timber – whether permanent or temporary (like scaffold boards) – always include a factor of safety; generally 2½ times the design load before any failure should occur. It is the material that has not been graded or inspected by a trained eye that we should be more worried about.
Stay Safe.
NB. Woodexperts are an independent company working to improve the use and reputation of timber and have no connections with organisations such as NASC. A lot of our work involves helping timber companies comply with regulation, especially the strength grading of timber in all areas of construction including roofing and scaffolding.
Wood is a natural material and has variable characteristics but it is good to know that all timber designs which involve strength graded timber – whether permanent or temporary (like scaffold boards) – always include a factor of safety; generally 2½ times the design load before any failure should occur. It is the material that has not been graded or inspected by a trained eye that we should be more worried about.
Stay Safe.
joebag
Well-known member
Thanks but ,,,,,
Thanks for the reply but for the moment I will sleep easy lol,it always amazes me how firms employ structual engineers,design consultants etc who work to nunmbers and exact formulae yet out of these same companies come baseless scaremongering about something that may or may not happen,yet have no evidence to back up these moneymaking scare stories,I can be pulled on a handrail that's mm too low,britains full of hse and why,,,,at the end of it just like agencies in our line of work,parasites making money off the back of it,not putting you in that basket just seeing the big picture!
Thanks for the reply but for the moment I will sleep easy lol,it always amazes me how firms employ structual engineers,design consultants etc who work to nunmbers and exact formulae yet out of these same companies come baseless scaremongering about something that may or may not happen,yet have no evidence to back up these moneymaking scare stories,I can be pulled on a handrail that's mm too low,britains full of hse and why,,,,at the end of it just like agencies in our line of work,parasites making money off the back of it,not putting you in that basket just seeing the big picture!