Principal Contractor Duties under CDM 2015
TL;DR
The principal contractor (PC) is appointed when there is more than one contractor on a project. The PC's core duty is to plan, manage, monitor and coordinate the construction phase — including preparing the Construction Phase Plan, managing worker welfare, and ensuring all contractors cooperate safely.
Who is the Principal Contractor?
The principal contractor is the organisation or individual responsible for managing the construction phase health and safety on a project that involves more than one contractor. They are appointed by the client and must be a contractor (not a designer or client-only organisation).
The principal contractor is distinct from the principal designer, who manages health and safety during the pre-construction phase.
What Must a Principal Contractor Do?
Before Construction Starts
- Prepare the Construction Phase Plan (CPP) — the CPP must be prepared before construction begins. It should address the significant risks identified in the pre-construction information and show how they will be managed. It does not need to be exhaustive at day one but must be suitable and sufficient.
- Review pre-construction information — the principal designer will provide a pack of information about the site, structure and known hazards. The PC must review this before starting.
- Agree welfare arrangements — toilets, washing facilities, rest areas, drinking water and changing areas must be suitable before workers arrive.
- Notify the HSE if not already done — the PC must ensure the F10 is displayed prominently on site.
During Construction
- Develop and update the CPP — the plan must grow as the project develops. New risks must be addressed. It should reflect current site conditions.
- Coordinate contractors — ensure all contractors cooperate with each other and comply with any rules set out in the CPP.
- Control site access — prevent unauthorised persons from entering the site.
- Consult workers — workers and their representatives must be consulted on matters that affect their health and safety. Toolbox talks and pre-task briefings satisfy this requirement when well-documented.
- Provide site inductions — all workers must receive a site-specific induction before starting work. Records must be kept.
- Monitor compliance — site inspections must be carried out regularly and documented.
- Manage incidents — the PC must ensure incidents and near-misses are reported, investigated and recorded. RIDDOR reportable incidents must be reported to the HSE.
- Liaise with the principal designer — the PC must share information relevant to the health and safety file.
At Completion
- Pass information to the principal designer — for inclusion in the health and safety file.
- Ensure outstanding welfare obligations are discharged — workers must not be left without facilities before practical completion.
The Construction Phase Plan in Detail
The CPP is the principal contractor's most important document. It must include:
- A description of the project and construction work
- The management structure and responsibilities
- Arrangements for welfare facilities
- How contractors will cooperate and communicate
- Procedures for emergency and first aid
- Site rules and access control arrangements
- Details of significant risks and how they will be managed
- Arrangements for checking compliance
The CPP is a living document — it should be updated as conditions change, new risks emerge, or additional contractors join the project.
Evidence the HSE Expects from a Principal Contractor
| Evidence | Frequency |
|---|---|
| Construction Phase Plan | Before start; updated throughout |
| F10 displayed on site | From day one |
| Worker induction records | Every worker, every site |
| Toolbox talk records | Regular, topic-specific |
| Site inspection reports | Weekly or as conditions require |
| RAMS received and reviewed | Before each significant task |
| Incident and near-miss records | As they occur |
| Welfare facility inspection records | Regular checks |
What Good Looks Like
A well-run principal contractor operation will typically show:
- A CPP that reflects actual site conditions and is updated after significant changes
- Induction records for every worker with signatures
- Toolbox talks with attendance sheets covering relevant topics before hazardous work starts
- Regular site inspection reports identifying issues and confirming close-out
- A prompt incident reporting culture with RIDDORs submitted within prescribed timescales
How Workforce Guardian Supports Principal Contractors
- Digital CPP — create and maintain your Construction Phase Plan within the platform
- Induction management — workers complete mobile inductions before arriving on site
- Toolbox talks — record delivery and attendance digitally with date and topic
- RAMS workflow — receive, review and approve contractor RAMS before work starts
- Incident reporting — workers report incidents from their phone; full RIDDOR workflow built in
- Evidence pack — compile all PC documentation for client handover or HSE inspection instantly
FAQs
Must the principal contractor be the main contractor?
Usually yes — the PC is typically the contractor with overall control of the site. However, on management contracts, the PC may be a management contractor rather than a works contractor. The key test is who has overall control of the construction phase.
What if a contractor refuses to comply with the PC's site rules?
The PC has authority to stop non-compliant work. They should document the non-compliance and give written instruction. If a contractor persistently ignores safety rules, the PC can remove them from site and should notify the client.
How detailed does the Construction Phase Plan need to be?
Proportionate to the project risk. A short, low-risk refurbishment might need two or three pages. A high-risk, multi-phase project should have a comprehensive CPP with specific sections for each significant risk area. The HSE's guidance says it must be "suitable and sufficient."
Does the PC need to produce RAMS for every task?
The PC should ensure that RAMS are produced for significant risks — typically by the individual contractors carrying out the work. The PC reviews and approves those RAMS and ensures workers are briefed before the task starts.
What is the PC's liability if a subcontractor has an accident?
The PC can be held liable if they failed to provide adequate supervision, failed to check competency, or allowed unsafe work to continue. The HSE will examine whether the PC's management system was adequate and whether it was being properly implemented.