Hi ASW

Your first post here, so welcome to the Forums.

I am somewhat puzzled as to why you think that the question you have asked is a "divisive issue", not least since you specifically frame it in the context of "designed scaffolds" rather than what in ye olden days were described as General Access Scaffolds in HSE guidance note GS15.

Before the first iteration of CDM this was a recurring issue.

However, CDM introduced a definition of "construction work" (that has been tweaked very slightly since CDM 1994".

That definition was largely based on the definitions in Section 175 of the Factories Act 1961 of a "building operation" and "work of engineering construction", but with the legislators taking the opportunity to close some perceived loopholes in the application of construction H&S legislation, including as regards the sort of question you are asking.

So the CDM definition of "construction work" in its various parts brings in the definition of "structure"

“structure” means—
(a) any building, timber, masonry, metal or reinforced concrete structure, railway line or siding, tramway line, dock, harbour, inland navigation, tunnel, shaft, bridge, viaduct, waterworks, reservoir, pipe or pipeline, cable, aqueduct, sewer, sewage works, gasholder, road, airfield, sea defence works, river works, drainage works, earthworks, lagoon, dam, wall, caisson, mast, tower, pylon, underground tank, earth retaining structure or structure designed to preserve or alter any natural feature, and fixed plant;
(b) any structure similar to anything specified in paragraph (a); (c) any formwork, falsework, scaffold or other structure designed or used to provide support or means of access during construction work,

So, assuming that you have some "construction work" going on, then there doesn't appear to be much doubt that any scaffold that is erected in associated with the "construction work" will be a "structure" within the meaning of CDM.

Then the question comes to what constitutes "design", and from there responsibilities on any "designer".

“design” includes drawings, design details, specifications and bills of quantities (including specification of articles or substances) relating to a structure, and calculations prepared for the purpose of a design;

“designer” means any person (including a client, contractor or other person referred
to in these Regulations) who in the course or furtherance of a business—     (a) prepares or modifies a design; or     (b) arranges for, or instructs, any person under their control to do so, relating to a structure, or to            a product or mechanical or electrical system intended for a particular structure, and a person            is deemed to prepare a design where a design is prepared by a person under their control;

I would note that compliance with CDM in relation to the design of scaffolds is probably very patchy, not least as this is usually done as part of Temporary Works (whether identified as TW or not) under the direction of the Principal Contractor or another Contractor and there might not be the appropriate level of oversight of this element of design by the Principal Designer.

However, that is an issue of implementation rather than intepretation of the Regulations where what CDM says seems very clear to me!

Perhaps the much bigger problem is where someone doesn't recognise the need for a "designed scaffold" and leave it to the scaffolders to get on with it. They they stray from erecting a straightforward scaffold due to the constraints they come across and do the "design" on the hoof.

As example there is a redevelopment happening at the building next door to where I live. So scaffolds up on front and rear elevations, in each case from basement well to 3rd floor level.

Problem is that at one end of the rear scaffold there is an outhouse which sits where the standards might have been expected to be. Couldn't found the scaffold on the outhouse as its roof is fragile to the point of very visible near collapse. 

So the solution found by the scaffolders was to foot the end standards on the party wall between two gardens. 

Should be patently obvious to all working on the project that this 19th Century wall was not designed for vertical loading and it seems that the scaffolders recognised this.

So to reduce the load down on to the wall, the upper lifts are in horizontal cantilever, so that most of the load is transferred to bear down on standards footed in the basement well.

It's possible that someone has actually sat down and produced a drawing to demonstrate that this affords an appropriate level of structural security - i.e there is a formal "design", but I am very doubtful that this is what happened!

Much more likely is that the scaffolders themselves have done an impromptu "design" to solve a problem. Seems to me that this is still a "design" within the meaning of CDM, with said scaffolders thence the "designer".

A Scaffold Design Engineer should design the scaffold, not to be confused with the Principal Designer for the project.

I would say yes whoever designs a designed scaffold is a designer under CDM.  It seems quite straightforwardly the case to me, whether that designer works for a scaffolder or a consultatnt.

It did cause some consternation and resistance when CDM first started that a contractor (general parlance) could be a Designer (under CDM), but I had thought that most parts of the industry had got that message by now.  Possibly it's less accepted among scaffolders.  I note that the scaffolders my company most often encounters are ones that have already decided they want an external designer (i.e. us) for the scaffold they are contemplating, so it's not for us contentious.

Hi again ASW

Follow up since you specifically asked but I think achrn's answer does most of the talking for me.

For some strange reason CDM has always thrown up some "confusion" or perhaps as likely "unwillingness" for one CDM duty holder to accept that they might also fall within the definition of another duty holder, even when they might not have intended this to be the case.

CDM (and the parent EC Directive for much of its content) is based on a period of time called the pre-construction phase, and another the "construction phase", where depending on where you are in Europe the word "phase" might be translated as "stage".

It is almost natural to assume that these are along a time line where one follows the other but it is the norm that there is an overlap such that activities associated with the "pre-construction phase" such as "design" continue into the "construction phase" AND/OR that further "design" etc occurs during that phase.

Without going into the detail the duties on the Principal Designer (and the Client) extend to a degree of oversight of "design" whenever it happens. 

So supposing the Principal Contractor instructs some Temporary Works design, or e.g. a scaffolding contractor instructs the design of a scaffold (TW though often not accepted as being such), this might take place without the Principal Designer being sufficiently aware. How much the PD actually needs to know will depend on the circumstances, inclusive of what the TW might mean in relation to future works and thence what should perhaps be highlighted in the Health and Safety File for a "structure".

However, if some scaffolding contractor engages an "independent safety advisor" who influences the said contractor into thinking that they have no responsibility for the "design" of a scaffold, then said contractor should probably be looking for more competent advice!

It doesn't actually matter for the purposes of CDM (rather than the BS on Temporary Works) whether you consider the scaffold (designed or not) to be Temporary Works as CDM doesn't actually mention TW, but instead "design". 

Sorry, ASW but we would have been typing at the same time!

I don't think the wording is so much "purposely vague" so much as NOT exclusive.*

Each case has to be considered on its individual merits, but in my mind a scaffolding contractor who instructs A N Other to do a scaffolding design is likely to be interpreted as themselves being a "designer" unless they were to manage to show that the "design" was somehow outside their control.

*For comparison look at Sections 2 and 3 of HSWA. 

Section 2(1) sets out a general duty on the employer towards their employees. Section 2(2) sets out examples of how that general duty pans out.

In contrast in Section 3, such detail is not spelled out. It doesn't follow that issues such as those cited in Section 2(2) do not apply to the employer's general duty towards persons other than their employees.

To be honest (and I am someone who has worked for a company which has benefitted hugely from CDM, and someone who has benefitted personally as a consequence) I never thought that there was a need for a specific code of regulations to adequately transpose the requirements of the EC Temporary or Mobile Construction Sites Directive into law in Great Britain, though fairly minor changes to existing law would have been needed.

TMCSD could have been transposed via perhaps an Approved Code of Practice or even just guidance to explain how the principles of HSWA and the Management of Health and Safety at Work Regulations 1992 (at the time) could be applied to construction projects.

So, if you were to ignore CDM entirely, and considered the duties of the Scaffolding Contractor under HSWA and MHSWR how would they wriggle out of having a degree of responsiblity for work done by a designer they appoint?

If you have ever done Venn diagrams, you could draw a large circle representing the "set" that is HSWA, a smaller circle wholly contained within the "set" that is the "subset" representing MHSWR.

Then a second smaller circle which is mostly contained within the "set" to represent CDM. The bits outside the main circle would be:

1. The requirements for notification as the process is wider in terms of duty holders to be covered than was previously the case with Sections 175(6) and 175(7) of the Factories Act 1961.

2. Part 4 of the Regulations which by and large are a consolidation of requirements previously within the four codes of Construction Regulations 1961 and 1966, then consolidated into the Construction (Health, Safety and Welfare) Regulations 1996 which neatly stood alongide the management requirements of TMCSD in CDM 1994.

Edited by user 16 July 2024 17:00:21(UTC)  | Reason: Formatting