Wednesday, 15 October 2008

Scaffolding Inspection

Hello everyone,

We have been recently asked whether there is a 'standard checklist' for scaffolding inspection and if so where can we get it. I have also seen this topic discussed on the HSE construction forum.

As it happens we are currently in the process of creating one, which, when finished will be available to download from our website, however this raises another question:

What experience/qualifications must you have to inspect scaffolding?

Around 2 years ago I attended a training course in Scaffolding Inspection in Wakefield run by a large training centre with a reasonable reputation. To say that it was a total waste of time would be accurate. At the time I had been designing scaffolding for around 2.5 years and thought that my depth of scaffolding knowledge was fairly good. The course itself was delivered by an unenthusiastic trainer who was regurgitating a set of out-of-date slides and handouts. We talked about the 'special scaffolds' in 5973 and that upon completion of the course you would be able to inspect them, we were given a 'design drawing' to look at (which was poor) and talked through how to read them. The questions delegates had went unanswered and in the end the trainer was looking to me to answer them.

There were people on the course with very little scaffolding experience, some didn't even know the difference between a transom and a ledger, while others were ex-scaffolders looking for a change in career.

This just makes me wonder if these people can attend a two day course and then go out and inspect scaffolding, where does that leave the clients/main contractors and sometimes scaffolding contractors that employ such independent inspectors? Do they all hold PI insurance to cover their work? Who verifies that they are capable?

OK they could probably do a reasonable job inspecting a 3 lift, 5 bay independent with no sheeting and tied properly etc. but how would they cope inspecting something of considerable size and complexity? Would they be able to read and understand a complex design drawing and then assess the scaffolding accordingly? Make assessments of the critical members, tie points, check fittings, beam supports etc. Is there anyone out there that could say: "Sorry, you do not have the experience/expertise to inspect this scaffold?"

I had a telephone call from an 'independent inspector' 2 weeks ago who was inspecting a scaffold that I had designed. He asked me why I specified 'transom centres at 915mm c/c instead of the usual 1200mm', he asked about why he would need to 'check' the fittings as surely they were manufactured to British Standards and why he would need to only check the rakers and not all of the scaffolding? I duly explained about load on working platforms and transom centres and that a check fitting wasn't literally checking the fitting. I then asked him how the RMD slimshores looked that were attached to the bridge pier using resin anchors and supporting about 85% of the scaffold.... to which he replied: "What RMD slimshores?"

I rest my case.

I would love to hear about your experiences with scaffolding inspectors that have left you baffled or gab-smacked or just with a general disbelief. Similarly, please let me know of anyone you have found to be on top of their game and a credit to the industry.

Hopefully our scaffolding checklist will be available shortly for you all to use.


Thursday, 18 September 2008

The Use of Aluminium Beams in Scaffolding

Hello everyone,

Firstly I would like to apologise for our lack of posts recently... we've had a very busy summer (if you can call it summer with the weather we've had!) and members of our design team have been on holiday so those remaining have been picking up the slack! Anyway, we're back now!

It seems to me that more and more people when erecting scaffolding incorporating aluminium beams are ignoring (or are not aware of) the requirements for bracing the beams set by the manufacturer
. I do not know of a single beam manufacturer that says their beams do not have to have top and bottom chord ties and at least a single row of plan bracing.

Often beams are used in loading bays, often directly under the working platform. That means 9/10 times the transoms on the top chord of the beam are on singles - not load bearing couplers! Sometimes, boards are laid directly onto the beams! (see photo)

This photo is of a scaffold on St.Pancras Station in London that I noticed whilst waiting for a taxi outside Kings Cross. Boards are laid directly onto beams, beams have no chord ties or bracing so 'technically' they are no better than a double scaffold tube. Not to mention the fact that the supporting independent looks dangerously slender and could fold like a pack of cards under any significant loading.

Load bearing couplers must be used to tie the top and bottom chords of aluminium beams in all scaffolding applications otherwise the beam can not be rated to the safe working load published by the manufacturer - more importantly, if the scaffold were to fail and the HSE were involved, the scaffolding erector would not have a leg to stand on!... and possibly others too such as the scaffolding inspector, hire company, main contractor... etc etc.

Aluminium beams are all different and each has their own bracing requirements, however, if you stick to these simple rules you won't go far wrong:

1. Compression chord (usually top chord) ties at 1.0m centres
2. Tension chord (usually bottom chord) ties at 2.0m centres
3 i. Beams up to 450mm depth - single row of plan bracing full length every 5th bay
ii. Beams over 450mm depth - double row of plan bracing full length every 5th bay
4. Lateral brace (dog-leg brace) every 2.0m in alternating directions.

The photo above is not a unique case, there are examples all over the UK of scaffolders misusing beams, there is one on a house extension opposite the school I coach basketball at where a 450 beam has no bracing, transoms on singles on the top boom supports the working platform and the beams must be spanning at least 6.0m!

The question I have for you is... what is to be done about it?

Do we report every scaffold we see that is not erected to 5973/TG20 or has beams not fixed correctly?
Do we try to inform the scaffolder or client of their mistakes?
Do we wait for someone to get hurt?

I would love to know your thoughts...

Bye for now.

Monday, 2 June 2008

May Gurney - High Level Bridge End of Contract Celebration

Hello all!

Just a quick post to give a big 'thank-you' to May Gurney for their invite to the High Level Bridge end-of-contract celebrations in Newcastle on Friday night.

We were treated to a really good 'do' and enjoyed great company, good food and brilliant entertainment!

A fitting end to a successful contract - thanks again May Gurney!


Monday, 3 March 2008

Scaffolding Design Appreciation Course - Information Available NOW

Hello everyone!

Information on our new training course entitled 'Scaffolding Design Appreciation' is now available from our website - CLICK HERE

We are now taking bookings for dates throughout the summer. Interest has been high and places are beginning to fill up so be sure to act quickly to avoid disappointment!

Thursday, 28 February 2008

Ground Conditions

Allowable bearing pressure of 50kN/m²?

In most cases, it is essential that the ground underlying and adjacent to a scaffold be assessed in some way to determine the safe bearing performance of the ground. I’ve heard of all kinds of different methods of testing soils from the ‘finger pressure test’ to borings and trial pits.

If you have been advised that the safe bearing pressure on site is 50kN/m2, I would like you to consider the following:

I weight 77kg and in every step I take, the contact area (footprint) of one shoe is approximately 0.01m². What is my ground pressure? The ground pressure is equal to my weight divided by the ground contact area, therefore my ground pressure load = 0.75kN / 0.01m².

Pressure exerted on the ground from one of my shoes = 75kN/m²

With the above in mind, I would be very careful next time you’re on a site with an allowable bearing pressure of 50kN/m² and watch every step you take... You may sink like quicksand!

Wednesday, 27 February 2008

Scaffolding Design Appreciation Course

Hello everyone!

This is a quick post to let you all know that the course information, dates and application forms for our long awaited Scaffolding Design Appreciation course will be available for download from our website from Monday 3rd March -

Places have been in high demand so far and we've not even confirmed the dates! We are expecting places to fill up quickly so you'll have to act quickly if you would like to be one of the first on the course!

See you soon!

Wednesday, 30 January 2008

43m Long Scaffold Bridge is BIG SUCCESS

Hello everyone,

Last night; Tuesday 29th Feb myself and Alwyn went to see the final lift of the 43m (141ft) scaffold bridge spanning over the A639 in Pontefract, West Yorkshire.

The scheme has been ongoing for a month or so now a
fter the original works were postponed in 2007. The Scaffold bridge was built off site by SYS (scaffolding) after being designed for May Gurney Rail by Alwyn Richards Temporary Works Design. The bridge was transported from the SYS yard in sections and fixed together at the side of the road by SYS before being craned into position last night. Scaffold towers support the structure at either end and overall stability is maintained by a cast concrete base. The bridge itself weighs around 72kN (7.2t) and is designed to carry railway cabling and a service load for access.

The whole process was a spectacular event, especially at night under floodlights with the road closed and one which required the full cooperation of May Gurney, SYS, Ainscough Crane Services and ourselves. Well done everyone.

The first photo shows the bridge during the lifting process and the second once the bridge had been located on the supporting towers.

More photographs and detail will follow on our website shortly.