CDM 2015 Summary of All Duties
TL;DR
CDM 2015 assigns specific legal duties to five duty holder categories on UK construction projects. This page summarises every duty, when it applies, and what evidence the HSE expects — in plain English.
What CDM 2015 Does
The Construction (Design and Management) Regulations 2015 set out a framework of duties aimed at ensuring health and safety is properly planned and managed throughout the whole project lifecycle — from the earliest design stages right through to completion and maintenance.
CDM 2015 places duties on everyone involved in a project, not just the principal contractor. The regulations make clear that safety must be coordinated across all parties, with clear lines of responsibility.
The Five Duty Holders
1. Client
The client is the organisation or individual for whom the construction work is carried out. They bear ultimate responsibility for the project's health and safety arrangements.
Client duties include:
- Appointing a principal designer and principal contractor when required
- Ensuring suitable arrangements are in place before construction begins
- Ensuring the construction phase does not start before the Construction Phase Plan is prepared
- Ensuring the health and safety file is prepared and passed on at project completion
- Notifying the HSE where the project is notifiable (F10)
What good looks like: Written appointments in place before work starts. Pre-start review confirming the CPP is adequate. Evidence of ongoing client engagement with the project's safety arrangements.
2. Designer
Designers include architects, engineers, and anyone who prepares drawings, specifications, or bills of quantities. Their duty is to eliminate hazards through design where reasonably practicable.
Designer duties include:
- Eliminate foreseeable risks to health and safety during construction and maintenance
- Where elimination is not possible, reduce and control risks
- Provide information about residual risks to the principal designer
- Ensure all designs comply with the general principles of prevention
What good looks like: Design risk register showing how hazards were considered and resolved. Residual risk information passed to the principal designer at handover.
3. Principal Designer
Required on projects with more than one contractor. The principal designer coordinates health and safety during the pre-construction phase.
Principal Designer duties include:
- Plan, manage and monitor pre-construction health and safety
- Coordinate with designers to eliminate or control design risks
- Ensure a pre-construction information pack is prepared and issued to contractors
- Prepare and maintain the health and safety file
- Cooperate with the principal contractor during the construction phase
What good looks like: Pre-construction information pack issued before tender. Health and safety file updated throughout the project. Evidence of coordination with designers and contractors.
4. Principal Contractor
Required on projects with more than one contractor. The principal contractor coordinates health and safety during the construction phase.
Principal Contractor duties include:
- Prepare, develop and implement the Construction Phase Plan (CPP)
- Organise cooperation between contractors
- Provide and maintain a suitable site induction
- Consult workers and their representatives
- Collect and keep welfare arrangements in place
- Prevent unauthorised access to the site
- Display the F10 notification on site
What good looks like: CPP prepared before construction starts and updated as the project develops. Induction records for all workers. Regular toolbox talks with sign-off records. Site inspection reports and incident logs.
5. Contractor
Every contractor working on a construction project has duties, regardless of whether they are the principal contractor or a sub-contractor.
Contractor duties include:
- Plan, manage and monitor their own work
- Ensure workers under their control are trained and competent
- Comply with directions given by the principal contractor
- Report anything that might affect health and safety to the principal contractor
- Ensure workers have the information and instructions they need
What good looks like: RAMS prepared and reviewed before work starts. Workers briefed on the RAMS and signed off. Any near-misses or incidents reported promptly.
Notifiable Projects
Projects lasting longer than 30 working days with more than 20 workers simultaneously, or exceeding 500 person-days, must be notified to the HSE before construction begins using an F10.
The client is responsible for notification, although this can be delegated.
Evidence the HSE Expects
| Document | Who Prepares It | When |
|---|---|---|
| F10 Notification | Client | Before construction starts |
| Pre-Construction Information | Principal Designer | Before tender |
| Construction Phase Plan | Principal Contractor | Before construction starts |
| Health and Safety File | Principal Designer | Handed over at completion |
| RAMS | Each Contractor | Before each significant task |
| Induction Records | Principal Contractor | When workers first arrive |
| Site Inspection Reports | Principal Contractor | Throughout construction |
| Incident Reports | All Duty Holders | As they occur |
How Workforce Guardian Helps
Workforce Guardian provides digital tools for every stage of the CDM cycle:
- CPP module — create, publish and update your Construction Phase Plan in one place
- RAMS generation — AI-assisted RAMS with digital worker sign-off
- Digital inductions — mobile-first induction with signature capture
- Incident reporting — RIDDOR-compliant, timestamped, with photo evidence
- Evidence pack — one-click compilation of all CDM documents for audit or handover
FAQs
Does CDM 2015 apply to refurbishment and maintenance work?
Yes. CDM 2015 applies to most construction work, including refurbishment, repair, maintenance, and demolition — not just new builds. The regulations apply to the construction, maintenance, renovation, repair, upkeep, redecoration or other alteration, decommissioning, demolition or dismantling of a structure.
Can one person be both principal designer and principal contractor?
No. The roles have different responsibilities and applying them to a single organisation would create a conflict of interest. They must be separate appointments, though in some cases the same company can provide both services through separate teams.
Do small projects need a full Construction Phase Plan?
Yes, but the level of detail should be proportionate to the project's risk. A simple low-risk refurbishment might have a one-page CPP. A complex multi-contractor build will need a comprehensive, regularly updated document.
What happens if a duty holder does not fulfil their CDM obligations?
The HSE can issue improvement notices, prohibition notices, and prosecute. Directors and senior managers can be held personally liable. Fines for CDM breaches can be substantial and unlimited in the crown court.
When should the CDM duty holders be appointed?
As early as possible. The principal designer should be appointed at the project design stage. The principal contractor should be appointed at or before tender. Late appointment is a common failing that leads to inadequate pre-construction planning.