Home > Uncategorized > Much Ado About Nothing?

Much Ado About Nothing?

Situation

When passing by the site offices I noticed the pulley system scaffolders had erected to speed their delivery of materials up a 12m viaduct wall, instead of using the stairs.  I didn’t take a second look at first, as it looked like a routine and simple operation that they would carry out on a regular basis and “they must well know what they’re doing” it’s their specialist trade as scaffolders.  However, I hadn’t previously checked their RAMS as this had been done by someone else so I was coming at this with a fresh pair of eyes.

Slide1

Options

  • Do nothing – it looks fine and is likely capable of lifting scaffold equipment. They must know what they’re doing.
  • Question the scaffolders to get a confirmation that they are using the correct methods and that they know what they’re doing – I know they’ll tell me what I want to hear.
  • Stop their works and do some checks. It just doesn’t look right.

I opted for the third one.

Issues

I used a method I recently learnt at a Multiplex 2 day quality training session I attended which included the use of fishbone diagrams for finding the root cause of nonconformities.  Dubious as I was to their use, it provided another variation to a mind map.  This gave me a number of routes to explore but I’m sure I will have missed elements out.

Fishbone

What appeared to be a simple situation can have a lot more to it as I found out:

  • Work not covered in the RAMS. I checked their RAMS which had been filled out for the works to be undertaken on top of the viaduct but had not included delivery method and movements of stores.  The RAMS had been checked but were not including the use of the pulley and therefore was not picked up.  If it had included the lifting operation then the lifting operations coordinator would have been included in the checking of the RAMS.  This means that the works shouldn’t have been carried out because they were not in accordance with the RAMS.  The conformity and signing up to the use of RAMS is done by each individual at induction on site.  This confirmed it was right to stop the works until the RAMS was amended and resubmitted for approval.
  • Scaffold incorrectly constructed/not appropriate. What appeared to be a simple pulley mechanism was lacking moment carrying capacity.  Looking at the setup I remembered portal frames and that if the load were to be transferred through 90 degrees, there would likely be a big bit of steel required at the haunch to deal with the induced moment.  But surely they know what they’re doing and the scaffold connection is designed to carry the load?  No – a diagonal member is required to carry the vertical load.  This was not in place.
  • Mechanism incorrectly fitted.  After googling the pulley brand, it turned out they were using it the wrong way round and the brake wasn’t working – this made me think there was a lack of training somewhere in this mix of issues and that there could be other issues regarding the training.
  • Knots.  Individuals using knots to secure loads to rope must be level 1 trained. The previous item made me wonder whether this was the case and so I requested proof of their training – handily held on a CSCS card, copies of which are retained during the induction process on site. It turned out the individual was correctly qualified.
  • Not valid document for pulley. The pulley itself was not provided with a test certificate. When asked to provide one there was a delay before a certificate was supplied.  It came from the scaffolders’ office and is likely to have been put together following that request.  However, there was no way of disproving this.

Slide2

Learning Points

I consulted the HSE website, LOLER and the pulley’s operating and maintenance instructions (links supplied below), and have put together the following key points for the correct set up and use of a scaffold pulley wheel:

  • The scaffold gallow bracket must be correctly erected (90 degrees with diagonal brace).
  • The horizontal tube from which the pulley wheel is suspended should be fixed with right angled couplers to both the inner and outer standards.
  • The Pulley wheel must have a fully functional brake (the braking action is compulsory and shall be automatic when the operating force ceases, whether the motion is lifting or lowering).
  • Ropes must be the correct size to suit each type of pulley wheel (usually 18mm).
  • If the rope has a hook attached for the purpose of lifting loads then it must be a safety hook, correctly spliced to the rope at point of manufacture.
  • The pulley must be tested and examined before use and every 6 months thereafter (certification to this effect must be issued.)
  • Weekly LOLER inspection of the wheel and rope must be undertaken by a competent person and the results recorded.
  • Materials must only be attached to the rope by an appointed loader handler who is authorized, with evidence provided that they have received the necessary information, instruction and practical experience, particularly in the types of knots used to secure loads (minimum requirement must be COT course, H&S test and CISRS Trainee Part 1 Pass).

Conclusion

The most frequent causes of incidents regarding pulleys relate to the inadequate attachment of the load to the rope, the incorrect attachment of the wheel itself and a non-functioning brake.  Specialist trades are assumed to know their methods of work and it is easy to think they have the definitive knowledge of a subject.  However, whilst implementing their skills at the lowest level they may be using equipment they haven’t touched for some time or are unfamiliar with.

References:

Gin Wheels Checklist

CAP 609 General Information Booklet

Requirements for all “thorough examination” documents

Scaffold CIRSR training booklet and website “Construction Industry Scaffold Record Scheme”

 

Categories: Uncategorized
  1. 25/08/2017 at 9:23 am

    Sounds like it would have been easier to take the stairs after all!

  2. 25/08/2017 at 6:48 pm

    I sometimes wonder whether generic management systems for management of standard operations may not over complicate things ;

    1 It’s a lifting operations
    2 There is a LOLER ACoP issued by H&SE – everything necessary is covered in plain English there
    3 Reg 4 is Adequate strength and stability- what seems sensible is to do what you’ve done and figure how it works as a structure. The one you show uses a single tube with an axial load and a moment applied ( not sure the top restraint is necessary in this case but the gallows bracket to the lower restrain punt certainly is) You still have a single tube with an axial load and moment applied (also check BE EN 1139 the min SWL for a tube coupler is about 6kN)
    Once a sensible structure exists why not include in the method statement an overloaded test lift- this might shortcut any detailed calcs

  3. Al Whiston's avatar
    Al Whiston
    25/08/2017 at 9:01 pm

    Hi Ed. As a point of interest, was there any repercussions for the operatives/subcontractor in respect to conducting works outside of their RAMS? Did they conduct a Point of Work Risk Assessment (POWRA) in order to cover this activity?

  4. Richard Farmer's avatar
    Richard Farmer
    30/08/2017 at 10:52 am

    Good call: Intrigued to know what the planned lift load was, you’ll get about 4kN with a diagonal strut before it exceeds the max coupler load. Also repercussions for the scaffolders for the flagrant introduction of H&S risk onto site. Or has it been written off by them as a pain the ar*e engineer making trouble, but don’t worry he’s back in his box now?

  1. No trackbacks yet.

Leave a comment