What is L144?
L144 is the HSE's Approved Code of Practice (ACOP) and guidance for the Construction (Design and Management) Regulations 2015 (CDM 2015). It provides detailed practical guidance on how all those involved in construction projects should manage health and safety throughout the project lifecycle.
CDM 2015 applies to all construction work in Great Britain, from small domestic projects to major infrastructure developments. The Regulations place duties on clients, designers, principal designers, principal contractors, contractors, and workers to ensure that health and safety is considered from the earliest project stages through to completion and handover.
L144 explains who has duties, what those duties involve, and how to discharge them effectively. It is the definitive guide to CDM compliance.
Who Needs This Document?
L144 is essential reading for:
- Commercial clients commissioning construction work
- Domestic clients undertaking home improvement projects
- Developers managing construction and refurbishment projects
- Principal designers coordinating design phase health and safety
- Architects and designers whose designs affect construction safety
- Principal contractors managing construction phase health and safety
- Contractors carrying out construction work
- Project managers overseeing construction projects
- CDM consultants advising on CDM compliance
- Property managers procuring construction and maintenance work
- Local authorities and public sector clients managing capital projects
Key Topics Covered
Who Has Duties Under CDM 2015?
L144 explains the duties of each dutyholder:
Clients:
- Make suitable arrangements for managing the project
- Ensure adequate time and resources are allocated
- Appoint principal designer and principal contractor (for projects with more than one contractor)
- Provide pre-construction information
- Ensure the construction phase plan is prepared
- Ensure the health and safety file is prepared and updated
Principal Designers:
- Plan, manage, monitor, and coordinate health and safety in the pre-construction phase
- Identify, eliminate, or control foreseeable risks
- Ensure designers comply with their duties
- Prepare and provide pre-construction information
- Liaise with the principal contractor
- Prepare the health and safety file
Designers:
- Eliminate hazards and reduce risks through design
- Provide information about remaining risks
- Consider buildability, maintenance, and demolition
Principal Contractors:
- Plan, manage, monitor, and coordinate health and safety in the construction phase
- Prepare and implement the construction phase plan
- Organise cooperation between contractors
- Ensure suitable site inductions
- Consult and engage with workers
- Ensure welfare facilities are provided
Contractors:
- Plan, manage, and monitor their own work
- Comply with directions from the principal contractor
- Provide information for the health and safety file
- Ensure workers are competent and supervised
Pre-Construction Information
L144 explains what pre-construction information must be provided by the client:
- Existing health and safety information about the site
- Information about existing structures (surveys, drawings, asbestos registers)
- Hazards relating to the site (ground conditions, contamination, services)
- Requirements for the project (phasing, access restrictions, occupancy)
This information enables designers and contractors to plan safely and price accurately.
The Construction Phase Plan
The construction phase plan is a key document required for all projects. L144 covers:
- When the plan is required
- What information it must contain
- How detailed it needs to be (proportionate to risk)
- How it should be used and updated during the project
- Who prepares it (principal contractor or contractor)
Key contents include:
- Description of the project
- Management arrangements
- Arrangements for controlling significant risks
- Welfare arrangements
The Health and Safety File
The health and safety file contains information needed for future work on the structure. L144 explains:
- Purpose of the file (informing future maintenance, repair, and demolition)
- What information to include
- When to hand it over
- Keeping it available and updated
Typical contents include:
- As-built drawings
- Design information and risk assessments
- Information about materials used
- Details of utilities and services
- Maintenance requirements
- Residual hazards information
Competence and Training
L144 addresses the competence requirements for all dutyholders:
- Organisational capability
- Individual competence
- Experience and track record
- Training and qualifications
- Resources and arrangements
Notification
Certain projects must be notified to the HSE:
- Projects lasting longer than 30 working days with more than 20 workers at any one time
- Projects exceeding 500 person-days of construction work
L144 explains notification requirements and procedures.
Domestic Clients
CDM 2015 applies to domestic projects, but with modified arrangements. L144 explains:
- Domestic client duties normally pass to the contractor (or principal contractor)
- Written agreement can transfer duties to the designer
- What this means in practice for homeowner projects
Legal Status
L144 has special legal status as an Approved Code of Practice. The ACOP sections give practical guidance on how to comply with CDM 2015. Following the ACOP is the clearest route to compliance.
If prosecuted for a CDM breach, failure to follow relevant ACOP provisions will be taken as evidence of non-compliance unless you can demonstrate equally effective alternative measures.
Why It Matters
Construction remains one of the most dangerous industries in Great Britain:
The Scale of Risk
- 30+ fatal injuries per year in construction
- Construction accounts for approximately 25% of workplace fatalities
- Falls from height remain the biggest killer
- Being struck by vehicles and objects causes many deaths
- Collapses and structural failures occur when risks are not managed
The Purpose of CDM
CDM 2015 exists to ensure:
- Health and safety is considered from the earliest project stages
- Designers consider how their designs will be built safely
- Projects are properly planned and resourced
- The right information flows to the right people
- Competent people are appointed
- Risks are managed throughout the project lifecycle
Consequences of Non-Compliance
For Clients:
- Criminal prosecution for failing to make suitable arrangements
- Civil liability for incidents caused by inadequate project management
- Project delays and cost overruns
- Reputational damage
For Designers:
- Criminal prosecution for hazardous designs
- Professional liability claims
- Professional body sanctions
- Reputational damage
For Principal Contractors and Contractors:
- Prohibition and improvement notices
- Criminal prosecution for unsafe working practices
- Civil claims from injured workers
- Loss of contracts and tender opportunities
Good Practice Benefits
Effective CDM compliance delivers:
- Safer projects with fewer accidents
- Better planned and more efficient work
- Clearer responsibilities and communication
- Useful information for future building management
- Demonstration of professional competence
- Competitive advantage in tenders
Key Document Summary
| Document | Purpose | Prepared By |
|---|---|---|
| Pre-construction information | Informs designers and contractors of known hazards | Client |
| Construction phase plan | Sets out how health and safety will be managed during construction | Principal contractor (or contractor) |
| Health and safety file | Information for future maintenance, repair, and demolition | Principal designer |
Dutyholder Summary
| Dutyholder | Key Duties | When Appointed |
|---|---|---|
| Client | Make arrangements, provide information, appoint dutyholders | Project inception |
| Principal designer | Coordinate pre-construction H&S, prepare H&S file | Before design work begins |
| Designer | Design safely, provide information on risks | When engaged for design work |
| Principal contractor | Manage construction phase H&S, prepare CPP | Before construction begins |
| Contractor | Plan and manage own work safely | When engaged for construction work |
Further Resources
- Construction (Design and Management) Regulations 2015 (legislation.gov.uk)
- HSE CDM web pages
- INDG411 - Want construction work done safely?
- Legal duties summary for clients, designers, and contractors
This page summarises the ACOP L144. For full legal compliance, obtain and read the complete document from HSE. This summary is not a substitute for professional advice or the full ACOP text.