CDM 2015
Duty Holder Guide


cdm 2015 Contractor

Every contractor involved in a construction project has duties under CDM. The main responsibility of a contractor is to plan and manage construction work under their control so that it is carried out in a way that controls risks to health and safety.

Contractors have important duties under CDM, and must also comply with the rules set out by the principal contractor. In this guide, we will take you through your responsibilities step-by-step. We will also link you to tools, resources and checklists to help you carry out your role.


A contractor may be an individual, a sole trader, a self-employed worker or a business who carries out, manages or controls construction work in connection with a business. Anyone who directly engages construction workers or manages construction work is a contractor. This includes companies that use their own workforce to do construction work on their own premises.

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Pre-Construction Phase
Before Construction Starts

The pre-construction phase is all the work that happens on a project before any work starts on site. This is the very earliest stage of a project and may also be referred to as the planning phase of the project. It's when designers and contractors are selected, and you plan and prepare for the project.


Contractors and anyone they engage to do work (subcontractors, workers) on a project must have the appropriate skills, knowledge, training and experience to do the work. Health and safety capabilities should be checked before they start work.

As a contractor, you and the workers under your control are those most at risk of injury and ill health on a construction project. You must secure your own health and safety and others, by influencing the way work is carried out.

CDM duties will apply to you as soon as you are appointed, including within the pre-construction phase before work starts on site.

Make clients aware of duties

As a contractor, you must not start work in relation to a project unless you are satisfied that the client is aware of their client duties under CDM.

Where you are the only contractor involved in the project you need to liaise with the client to assess this. You can check the client is aware of their duties through early meetings or project discussions with the client.

On projects with more than one contractor, the client must appoint a principal designer. On these projects, the principal designer will inform the client of their duties. You should check who the principal designer is, and seek confirmation from the principal designer that the client has been made aware of their duties.

Where the project is notifiable, check that the client has completed and submitted an F10 notification. Use our free CDM notification calculator to check if the project needs to be notified.

If you are working for a domestic client, some of their duties transfer to other members of the project team.

Cooperate with other duty holders

All contractors have a part to play in ensuring that the site is a safe place to work.

Contractors must cooperate with each other and share information on the risks involved in their risk that could impact other members of the team, and the controls in place to reduce risks.

On projects with more than one contractor, you will need to coordinate the planning, managing and monitoring of your work with the principal contractor and other contractors. Regular meetings will help ensure your arrangements remain consistent with the project wide arrangements.

You will need to comply with any directions and instructions for health and safety given by the principal contractor and principal designer.

The construction phase plan

For projects involving more than one contractor: The principal contractor will develop the construction phase plan. You will need to comply with any parts of the construction phase plan relevant to your work.

For single contractor projects: Where you are the only contractor and there are no other contractors or subcontractors involved in the project, you must prepare a construction phase plan which describes how health and safety will be managed during the construction phase.

The pre-construction information you have received and any client requirements you have established will help in drawing up the construction phase plan.

The construction phase plan should be proportionate to the size and nature of the work, and the risks involved, workable and realistic, sufficiently developed to allow work to start on site and regularly reviewed and added to as new trades start.

The following topics should be considered in the construction phase plan:

  • Project information including description and key dates
  • Key members of the project team and contact information
  • Health and safety aims and expectations
  • Site rules
  • Arrangements for cooperation and coordination of work
  • Arrangements for involving workers
  • Site induction arrangements
  • Provision of welfare facilities
  • Fire and emergency procedures
  • Control of site safety risks
  • Control of site health risks

As the sole contractor, you will be responsible for preparing the construction phase plan before setting up the construction site and starting work.

You may need to update the plan with further information as it becomes available, but it is important to make sure that early issues such as mobilisation, site set-up, welfare and high risk activities are addressed in the plan before work starts.

Advise on time and resources

Clients have a duty to allocate sufficient time and other resources.

Contractors can assist with estimating the period of time required to complete work or work stages during the pre-construction phase, as they may have a better knowledge of the time requirements at key stages of the project.

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Construction Phase
When Work Starts On Site

The construction phase is when work that has been planned begins on site. It's when the site gets set up and the construction work could include demolition, maintenance and/or building activities.

Appoint and engage workers

When appointing workers, you must make sure they have the skills, knowledge, training and experience needed to carry out the work safely. You should assess training needs and provide further training as necessary.

Information on health and safety risks including relevant parts of the construction phase plan needs to be communicated with workers through induction and worker engagement.

It is also a duty of contractors to provide appropriate supervision, instructions and information to each worker.

Provide instructions to your workers on what needs to be done and, importantly, how you intend the work to be done, in which order and with what equipment, especially when it involves high levels of risk. You should also ensure your workers know what to do in the event of an emergency.

Consultation with workers is key to the successful management of health and safety on site. It should be a clear two-way process, giving an opportunity for both parties, or their safety representatives, to contribute to decision making.

Talk to workers about:

  • Risks arising from their work
  • Hazards and risks from the surrounding environment
  • Ideas for managing risks
  • Ways of providing information and training

Meaningful consultation with workers will help raise commitment to health and safety, and workers can help you identify risks on site, make sure controls are practical and provide ideas for improvement.

Brief your workers on what is expected of them, and consider any suggestions from them on better ways of working.

Ensure welfare facilities are provided

For projects involving more than one contractor: The principal contractor has overall responsibility for ensuring welfare facilities are provided, you should discuss and agree with the principal contractor what welfare facilities will be available on site.

For single contractor projects: Where you are the only contractor you are responsible for ensuring welfare facilities are available.

Welfare facilities must be available from the commencement of work on site and remain until the construction work is completed.

Existing facilities may be available and suitable. If not, a mixture of both existing and new, or temporary welfare facilities, will need to be provided on site.

Welfare facilities should include:

  • Toilets - lit and ventilated, suitable for men and women
  • Washing facilities - next to the toilets, including hot and cold running water, soap, and a way of drying hands
  • Supply of drinking water and cups
  • Facilities for rest including tables and chairs
  • Changing rooms and lockers where required

Welfare facilities must be regularly cleaned and have sufficient capacity for the expected number of workers on site.

Ensure site inductions are provided

For projects involving more than one contractor: The principal contractor must ensure every worker is given a suitable site induction. You will still need to provide a suitable site induction where this has not been provided by the principal contractor.

For single contractor projects: Where you are the only contractor you are responsible for providing a suitable site induction to each site worker before they start work on the project.

The induction should be site specific and highlight any particular site risks and the control measures those working on the site need to know about. It should be relevant to the size and scope of the work, and level of risk involved.

The induction should include:

  • Project details
  • Management details and arrangements
  • Management commitment to health and safety
  • First aid arrangements
  • Accident and incident reporting requirements
  • Arrangements for health and safety briefings and toolbox talks
  • Consultation arrangements
  • Workers responsibilities
  • Site specific risks and arrangements

You should also provide site inductions to those who do not regularly work on the site, but visit occasionally or on a once only basis. You can tailor the induction to the nature of the visit, for example if you will be escorting a visitor around the site, they will only need to be aware of the main hazards they may be exposed to and the control measures in place.

Prevent unauthorised access

You must start work on any site unless reasonable steps have been taken to secure the site and prevent unauthorised access.

For projects involving more than one contractor: The principal contractor will have overall responsibility for site security, you must comply with their instructions and procedures. You should check that reasonable steps have been taken to prevent unauthorised access and liaise with the principal contractor about authorised access areas.

For single contractor projects: You must do whatever is proportionate to prevent unauthorised access to the site. Security measures need to be in place before starting work on the site and remain in place throughout the project.

When working in occupied or shared premises you will need to encourage close cooperation between the client and others to achieve this objective. The site boundaries should be clearly marked out using suitable means, depending on the size and nature of the project.

Provide management and supervision

You must ensure that you and your workers comply with directions from the principal contractor and the parts of the construction phase plan that are relevant to your work.

Contractors should monitor their work to ensure that the health and safety precautions are appropriate, remain in place and are followed on site.

You should:

  • Make sure that anyone engaged to carry out work is capable of doing so safely
  • Ensure that effective health and safety measures are put in place to control the risks
  • Make sure the right plant, equipment and tools are provided to carry out the work

You must ensure that appropriate supervision is provided.

Contractors must ensure that those managing and supervising the work have the right blend of skills, knowledge, training and experience and that there is an adequate number of supervisors.

The supervisor should be familiar with the type of work planned. The level of supervision required should take into consideration the skills, knowledge, training, experience and likely behaviour of the workers.

For projects involving more than one contractor: You have a duty to cooperate with other duty holders, and should provide the principal contractor with any relevant information from your monitoring so that information from all contractors can be used to manage health and safety at a project wide level.

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Post-Construction Phase
Project Completion

The post-construction phase is what happens at the end of the project. This may also be referred to as the handover phase of the project. It's when the construction work finishes and the project is signed-off and handed over the client.

Provide information for the health and safety file

For projects involving more than one contractor: The principal designer is responsible for preparing the health and safety file and you will need to provide the principal contractor with any relevant health and safety information to pass on to the principal designer for inclusion in this document.

While contractors do not have any specific duties in relation to the health and safety file, you must comply with any directions given by the principal designer and principal contractor.

Information should only be provided for inclusion in the file if it is needed to ensure the health and safety of anyone carrying out any future construction, demolition, use, cleaning or maintenance work on the building or structure.

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