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Duties of Principal Contractor

CDM (GB) Knowledge Base


The principal contractor has a central role in managing health and safety during the construction phase. It is achieved mainly by developing a Construction Phase Plan from the pre-construction information identified and collated by the Principal Designer and provided by the client and the designers, and by ensuring that the plan is followed.

Under CDM2015, regulation 13 sets out the duties the principal contractor has during the construction phase. Their main duty is to plan, manage, monitor and coordinate the work of the phase. Other duties include making sure suitable site inductions and welfare facilities are provided.

The principal contractor must be a contractor. A contractor is someone who performs or manages construction work and has been formally appointed as principal contractor by the client. The principal contractor is then also a contractor and must also comply with the contractor's duties.

Why is a principal contractor important?

Good management of health and safety on site is crucial to the successful delivery of a construction project. In liaison with the client and principal designer, principal contractors have an important role in managing the health and safety risks of the construction work.

Duties of Principal Contractor - Checklist

Principal contractors must:

The principal contractor has the major responsibility for safety and health during the construction phase on notifiable projects only, and has the duties to plan, manage, monitor and coordinate the construction phase taking into account the general principals of prevention to ensure:

  • Safety & Health - the project is carried out without risks to health or safety.
  • CPP - to be drawn up as soon as practicable prior to setting up a construction site and updated, reviewed and revised so it continues to be sufficient.
  • Coordination of the implementation of the relevant legal requirements to ensure that the employers etc. apply the general principals of prevention in a consistent manner and follow the CPP.
  • Contractor training etc. - where appointed ensure the necessary information, instruction, and training is received and appropriate supervision to comply.
  • Cooperation with others - cooperate with any other person at the site or an adjoining site to enable others to perform their duties etc.
  • Site rules - draw up.
  • Welfare - ensure compliance throughout the construction phase.
  • Liaison with PD - for the duration of the project and in particular regarding any information which is needed to prepare the H&SF or may affect the planning and management of the pre-construction phase.
  • H&SF - is appropriately updated, reviewed and revised from time to time.
  • Site Inductions - provide.
  • Unauthorised access - prevent.
  • Workforce cooperation - arrangement which will enable the PC and workers to cooperate effectively in promoting and developing measures to ensure health & safety at work and checking effectiveness.
  • Workforce consultation - consult workers in good time on matters connected with the project which may affect their health, safety or welfare.
  • Workforce communication - ensure workers can inspect and take copies of certain information.
  • Display the project notification on the site.

Competence and resources

As with contractors, the principal contractor must verify the competence and resources of his own personnel working on the project and any sub-consultants and sub-contractors that he engages on the project.

When assessing the competence and resources of the principal contractor team, the team should be assessed for its capability to perform the principal contractor's duties, taking in to account the specific requirements of the project.

Construction phase plan

The principal contractor has an absolute duty to prepare the construction phase plan prior to construction commencement, and develop, communicate, implement and amend the plan as necessary to maintain its sufficiency to effectively plan, manage and monitor the construction work. This should ensure that the work is performed, so far as reasonably practicable, without risks to health and safety.

Plan and manage the construction processes

The principal contractor has an absolute duty to plan, manage and monitor the construction such that the work is performed in a safe and healthy manner, so far as reasonably practicable. As part of this, the principal contractor shall facilitate co-operation and co-ordination between contractors, and designers if required, and the application of the general principles of prevention.

To achieve this obligation, the principal contractor must review the risk assessments and written safe system of work (method statements) produced by the various contractors engaged on the project to ensure that:

  • they are safe and comply with health and safety law and standards;
  • adequately describe the safe method of working; and
  • will not cause additional risk to themselves or others due to interactions with other activities being performed in the same place at the same time.

The principal contractor needs to monitor the way in which the work is being carried out to ensure that the precautions and rules specified in the construction phase plan are being followed. The monitoring will also establish whether the precautions prescribed are effective in the elimination, reduction and control of risk. Without any monitoring, the construction phase plan may not adequately control the processes and the associated risks. This does not mean that the principal contractor must directly supervise other contractor's work.

In planning, managing and monitoring the health and safety of the site the principal contractor must give detailed consideration to:

  • emergency arrangements and procedures (e.g. fire, bomb threat, means of escape, evacuation, confined spaces)
  • use and shared use of work equipment (e.g. cranes hoists, lifts, suspended access)
  • coordinating contractor activities so that they do not create hazards for each other

As part of the arrangements for managing site health and safety, the principal contractor on all projects will need to include within the construction phase plan the:

  • Fire risk assessment and fire safety plan for the site;
  • The site traffic management plan, ensuring so far as is reasonably practicable that pedestrians within the site are segregated from transport and plant; providing site rules for the movement of transport and plant where this segregation has not been achieved, e.g. bankspersons and high visibility clothing;
  • Waste management arrangements, which for projects that have a construction value of more than £300,000 will be contained within the Site Waste Management Plan, as required by the Site Waste Management Plans Regulations 2008 (SWMP). It should be noted that the principal contractor appointed under CDM may not be the same principal contractor appointed under the Site Waste Management Plans Regulations, although it makes sense for this to be the case. The appointments of CDM principal contractor and the appointment of the SWMP principal contractor must both be made in writing by the client.

The Principal Contractor must also ensure that other contractors plan, manage and monitor their own work, including performing inspections and audits.

Monitoring is performed both proactively and reactively. The proactive monitoring would involve site tours, inspections and audits, with reactive monitoring being the investigation into the causes of accidents and incidents that occur on the site.

To enable the principal contractor to comply with this requirement, contractors have a duty to inform the principal contractor of any accident of incident that is reportable to the HSE under the Reporting of Injuries, Diseases and Dangerous Occurrences Regulations 1995 (RIDDOR). However, it would also be useful for the principal contractor to be informed of other, non-reportable, accidents and incidents. This could be instructed under contract or as part of the construction phase plan.

Welfare facilities, unauthorised access and site rules

The principal contractor must ensure that adequate welfare facilities are provided for the site personnel. These facilities may be provided by the contractors, but the principal contractor must ensure that they are, and remain adequate, including the requirement to keep them clean and tidy.

The principal contractor is responsible for ensuring that unauthorised access to the site is prevented. The precautions to be taken to prevent unauthorised access will be commensurate with the risk. When construction work is carried out inside offices, factories docks etc., the existing security arrangement may deny undesirable access to the premises as a whole and steps may have to be taken to secure the site within those premises. In town centre sites, the proximity of members of the public is clear and hoardings and site security can be used to keep unauthorised persons out of the site. In high risk activities, the precautions may have to be significantly more onerous than on normal construction sites. Reference should be made to Health and Safety Executive guidance note HSG151, "Protecting the public: Your next move".

The principal contractor must also formally authorise people to enter and work on the site, either individually or in groups. This is normally achieved by performing site inductions and the checking the competence of individuals, such as checking the training and qualifications of such persons as scaffolders, plant operatives, electricians, etc.

The site rules will be specified by the principal contractor, and possibly the client and/or the Principal Designer, and documented within the construction phase plan. The site rules, along with other relevant parts of the construction phase plan, will be provided to all of the contractors' management, and explained to the operatives during the site inductions.

The principal contractor must then perform the management function of verifying that the rules are being followed by all persons involved in the project, including any visitors to the site. This would normally be achieved by regular site tours, health and safety inspections and health and safety audits.

The actions that the principal contractor will take in the event of a non-compliance with the site rules would also have to be specified. The principal contractor has powers to give reasonable directions to contractors, and the CDM2015 regulations requires contractors to comply with the principal contractor's reasonable directions and the site rules.

Providing suitable site inductions

The principal contractor must ensure a suitable site induction is provided to every site worker and the induction should be site specific and highlight any particular risks (including those listed in Schedule 3 of the CDM guidance) and control measures that those working on the project need to know about. The following issues should be considered:

  • senior management commitment to health and safety;
  • outline of the project;
  • management of the project;
  • first aid arrangements;
  • accident and incident reporting arrangements;
  • arrangements for briefing workers on an on-going basis e.g. toolbox talks;
  • arrangements for consulting the workforce on health and safety matters;
  • individual worker's responsibility for health and safety.

Site inductions should also be provided to those who do not regularly work on the site, but who visit it on an occasional (e.g. architects) or once-only basis (e.g. students). The inductions should be proportionate to the nature of the visit. Inductions provided to escorted visitors need not have the detail that unescorted visitors should have. Escorted visitors only need to be made aware of the main hazards and control measures.

Availability of key documents

The principal contractor shall make available to the other contractors key documents, which would include, as appropriate, health and safety file information, site surveys, designers' information, other contractors' risk assessments and the construction phase plan, as relevant to their management of the work.

Mobilisation time

The principal contractor must inform other contractors of their mobilisation time, which should be sufficient for them to properly plan their work and organise their resources.

Consultation, inductions, information and training

The principal contractor must make arrangements or ensure that contractors' arrangements are satisfactory for consultation with the workforce health and safety matters, the provision of suitable site health and safety inductions, health and safety information and on-site health and safety training.

The views of the workforce on health and safety aspects of the work and the site need to be sought by the principal contractor. This is an extremely important element of any effective health and safety management system.

The method of involving the workforce on the site and obtaining their views will need to be established in the construction phase plan and the workers informed of these methods during site inductions. For sites with a small number of workers on site it would be possible to perform the consultation on an individual basis. For sites with a large number of workers, seeking individual views by the principal contractor may not be reasonable and a system of representation and committees would need to be established. If representatives are to be used, they should be elected by the workforce, trained to act as representatives and the workers need to be informed the identity of their representative.

The principal contractor would normally ensure that the site rules are provided to all persons at work on the site by performing site inductions, which would also inform the workers of site hazards that are significant or unusual. The workers training and qualifications should also be verified before they were allowed to work on the site (authorised persons).

Liaise with the Client

The principal contractor should also work with the client to ensure there is cooperation with others outside the construction site who may be affected by the activities on-site. This includes co-ordinating the activities of contractors on the principal contractor's site with contractors on any neighbouring sites, particularly where the activities on each site combine to create hazards outside the sites that need to be addressed jointly.

Liaise with the Principal Designer

The principal contractor must liaise with the Principal Designer for any design undertaken during the construction phase and provide the requested information for the health and safety file. The principal contractor must supply the Principal Designer with information regarding the construction work that the principal contractor and other contractors are performing that would be required for the health and safety file. This information should have been previously specified as to the requirements in the pre-construction information and the methods to be applied for the collection of this information included in the construction phase plan.

The information needs to be supplied to the Principal Designer promptly, i.e. the provision of information should be on-going during the construction phase of the work. Only information on the later work should be supplied subsequent to construction completion. The accuracy of the as-built information is the responsibility of the contractor providing the information.

Display the Project Notification

The project notification, signed by the client and sent to the HSE, must be displayed on the site by the principal contractor at all times that the construction work is being undertaken. To achieve the requirement for all people working on the site and any other person affected by it to be able to read the project notification, it would be normal to post this within the welfare facilities and at the site entrance.

See Also