The Construction (Design and Management) Regulations 2015, CDM, were written with construction sites in mind, and process plant is rarely that tidy. The work happens inside a facility that is still producing, the scaffold goes up next to a live line, the tie-in sits in a shutdown window that cannot move, and the contractors arriving on Monday need to understand hazards that have nothing to do with construction and everything to do with what is in the pipe. On any project with more than one contractor, somebody must be formally appointed to hold that together.

We take the Principal Designer and Principal Contractor duty holder roles on process engineering projects, separately or together. Taking both is often sensible on plant work, because it removes the argument about whether a hazard belonged to the design phase or the construction phase. What we bring that a general construction duty holder may not is familiarity with the operating environment: hazardous area classification, permit systems, isolation and lock-off, hot work near flammable inventory, and the discipline required on a COMAH establishment where a construction activity can become a process safety issue.

What the duty holder roles involve

As Principal Designer we plan, manage and monitor the pre-construction phase. That means coordinating the design team so health and safety is considered at each stage, influencing the design to remove risk rather than simply record it, and challenging arrangements that push hazard onto the people who will build, operate and maintain the plant. Working at height, confined space entry and exposure to residues are cheaper to design out than to control later. We prepare or review the Pre-Construction Information, make sure it reaches everyone who needs it, record design and risk decisions as they are made, and build the Health and Safety File for handover.

As Principal Contractor we plan, manage and monitor the construction phase. We produce and maintain the Construction Phase Plan, set site rules, run inductions and access control, and coordinate every contractor so that one trade’s method does not create a hazard for another. On an operating site that also means working inside your permit to work system rather than a parallel one, agreeing isolation boundaries with operations, and controlling logistics, deliveries, welfare and temporary works within the footprint you can spare. We monitor, inspect, investigate near misses and report honestly rather than defensively.

What you get

  • Formal appointment as Principal Designer, Principal Contractor or both
  • Pre-Construction Information prepared or reviewed and issued to all parties
  • A project-specific Construction Phase Plan, kept current as works change
  • A design risk register showing what was eliminated, reduced, and left to be controlled on site
  • Site rules, inductions, access control and coordination of all contractors
  • Interface management with your permit to work and isolation procedures
  • Inspection, monitoring and incident reporting through construction
  • A complete Health and Safety File at handover, usable for future modification

When clients typically call us

  • A project has more than one contractor and no competent duty holder has been appointed
  • A shutdown is approaching and several contractors will share the same area
  • A tie-in to live plant needs designing and executing without a loss of containment
  • The site is a COMAH establishment and the works must sit inside the existing safety regime
  • An in-house team is carrying the duty holder role without the capacity to hold it
  • An audit or insurer review has found gaps in CDM documentation

Frequently asked questions

Does CDM apply to a small plant modification?

Very often, yes. CDM applies to construction work generally, including maintenance, modification and decommissioning, not only new build, and the appointments are triggered where more than one contractor is involved. If you are unsure whether a package qualifies, ask before it starts.

Can you take both roles on the same project?

Yes, and on process plant it often makes sense. It keeps design intent connected to site reality and removes the gap that opens when the two phases sit with different organisations. Where you prefer separation, we will hold one role and work alongside whoever holds the other.

How do you work on a site that keeps producing?

By planning around your operation instead of ours. Access, isolations, hot work and lifting are agreed with your operations and process safety teams, work is sequenced into the windows genuinely available, and the Construction Phase Plan reflects plant hazards as well as construction hazards.

Do your engineers hold hazardous area competence?

Our engineers hold CompEx certification, which is a competency held by individuals rather than a company accreditation. It supports work in areas classified under DSEAR and ATEX, where installation and inspection standards matter as much as the design.

Related: Part of our site and construction management services. See also construction design management (CDM).

If you have a shutdown, tie-in or modification coming up and the duty holder question is still open, it is worth settling early. Talk to us about your project. Request a call