With the HSE embarking on a new construction inspection initiative this coming week, focusing on dust, we are discussing our position as CDM Principal Designer.

I have seen a number of presentations on what the HSE expect the Principal Designer and Designers to do to eliminate dust when cutting slabs, bricks, roof tiles etc. We do get the message but are struggling with the practicalities.

The HSE have said they intend to track back on site dust hazards to Principal Designers and Designers and if required intervene (issuing formal notices, FFI, prosecute). We have no idea what they expect us to do to show compliance, proportionality or if we would be jointly liable for a designer’s failure, which includes clients.

As Principal Designer we would only challenge a designer if we believe a significant amount of dust would be produced and would normally rely on each designer to consider dust as part of their design. This is further complicated by the fact we do not appoint the designers, designs are often not progressed to such a fine detail and on design & build contracts the decision on for example paving slabs is often left to a subcontractor working with a generic specification.

I have retrospectively looked at a housing scheme and the requirement for paths to be a minimum of   900mm wide. You could use a 900mm wide slab but this will encounter a manual handling hazard. Dropping to a 600mm wide slab involves cutting, so you drop to a 450mm wide slab.  However this is social housing and for good reason (maintenance, appearance, durability) the client wants the whole area paved with slabs which will involve cutting regardless of what size is used. This decision along with numerous others was not recorded.

Are we expected to analyse their design which would be a huge task?

Picking up on Chris' point, surely the Principal Contractor is the one who is responsible for ensuring a SSOW, including the control of dust. For example, the design may include floor tiles/slabs, but it does not specify how they are cut, inside/outside, with what machinery, whether water is used to supress dust or other mechanical extraction systems. The designer cannot know all these variables in advance of the work.

The issue highlighted in my opinion is not simply about dust but about roles and responsibilities for risk management. 

The HSE are focused on front end risk management.  No issue with this and exactly where risk can/should be eliminated etc. 

However the PD is not some all-conquering, all knowing, all seeing body with the mandate of controlling every single construction risk that may arise. 

As long as the PD and designers are actively challenging each other at planning stage through collaborative risk reduction techniques such as RAG lists, DRR review and HAZIDs etc then this should be sufficient.  The PC will be expected to manage certain risks when construction begins. 

One further technique is to get the PC to challenge the DRR prior to construction.  You then have documented evidence that the PC is happy to manage the residual risk and confirms there processes to do so.