Last reviewed 23 September 2020

Andrew Christodoulou examines the critical role of supervision in accident prevention on construction sites.

On construction sites large and small, supervision has a key role to play in preventing accidents. Typical supervisory functions include planning and allocating work, making decisions, monitoring performance and compliance, providing leadership and building teamwork, and ensuring workforce involvement. Supervision is therefore heavily involved in the running of a typical construction project and in particular in ensuring that health and safety is effectively managed.

The Health and Safety Executive (HSE) has identified supervision as a ”Performance Influencing Factor” when attempting to prevent accidents (see the HSE website). It has also been a factor in a number of major high profile accidents in the past, such as the Piper Alpha oil rig fire in 1998 and the explosion and fires at the Milford Haven oil refinery in 1994. The lack of proper provision of supervision also regularly features as an important contributory factor in less well-known accidents, including many of those occurring on construction sites.

It is not, however, always viewed a critical factor for site safety and its provision is not always given the due consideration and weight it deserves. Sometimes supervisors, for whatever reason, do not fulfil their role effectively.

Legal aspects

The Health and Safety at Work, etc Act 1974 (HSWA), s.2(2)(c), places a duty on employers to provide “such information, instruction, training and supervision as is necessary to ensure, so far as is reasonably practicable, the health and safety of his employees”.

Supervisors themselves have a legal duty under s.7 of the Act to take reasonable care of themselves and others. Failure to supervise properly and effectively can lead to the prosecution of supervisors. For example, in 2008, as reported by the HSE, David Swindell Junior, a contracts manager, employed by 3D Scaffolding Ltd, was found guilty of breaching s.7 of the HSWA following the death of an apprentice scaffolder that he was supervising. Steven Burke, who was17 years old, fell 18 metres to his death.

There are additional legal requirements relating to supervision, as contained in the Construction (Design and Management) Regulations 2015 (CDM 2015). Regulation 4 requires clients to make suitable arrangements for managing projects. While “supervision” is not specifically mentioned, supervision is an established and standard feature of the management of health and safety.

In regulation 12, CDM 2015 requires principal contractors to plan, manage and monitor the construction phase of the project and co-ordinate matters relating to health and safety. Again, this must include consideration of the role of supervision.

Despite the legal requirements to provide supervision, there is no definition in the HSWA or supporting regulations as to what comprises supervision. The now removed Code of Practice to the 1974 Act did state that “good supervision is vital in health and safety terms for spotting potential hazards and ensuring that safety rules are complied with”.

What is supervision? How is it delivered? How much is required? All of these questions are left to employers and managers to decide. Whatever definition is taken or used, the importance of supervision remains a critical consideration and plays a key role in ensuring that the management arrangements put in place by the client and the contents of the construction phase plan developed by the principal contractor are achieved and maintained.

Who, how and how much?

The level and nature of supervision required should be determined as an outcome of the client’s management arrangements for the project and from the risk assessments carried out by contractors and others.

It is not sufficient to stipulate that “supervision will be provided” without specifying the detail of that provision. The client’s arrangements for managing the project and the risk assessments for the project should stipulate the level and nature of the supervision required.

Questions such as who will supervise, how supervision will take place, how much is required and when need to be considered. Some workers and some activities will require more supervision than others. For example:

  • young inexperienced workers may need very close and maybe constant supervision

  • migrant workers with poor English language skills, or understanding of site safety standards, may need additional supervision

  • high-risk activities will need to be closely monitored by supervisors.

Senior management commitment

Senior management must visibly support supervisors and their role. They must also show positive commitment to site supervision through, for example, sufficient financial investment in supervision.


The Health and Safety Executive Research Report (RR) 367 concluded that there is a positive correlation between attitudes and behaviours displayed by leaders and the development of a safety culture and safety climate.

Supervisors need to show leadership and they need to set a good example to others in both their actions and attitudes.

This is based upon the social exchange theory, which argues that ‘followers’ who enjoy high-quality relationships with leaders reciprocate the relationship by behaving in ways which the leaders appear to value. A literature review found evidence that employees in high risk professions behaved more safely in organisations where the leaders demonstrated they valued such behaviour than in work environments in which the safety climate was not so positive.


Effective communication between employees, supervisors and management is important within an organisation’s supervisory arrangements because of the positive effect that it has on safety performance.

The fundamental goal of health and safety communication is to provide meaningful, relevant and accurate information, in clear and understandable terms to specific stakeholders. This in turn can promote awareness and understanding of the management of health and safety as well as specific risk issues.

Employee involvement

Supervision can be important for achieving employee involvement, and often the supervisor can be the link between workers and site management. This can lead to improved health and safety standards on site.

Clear roles and responsibilities

If employees, supervisors and team leaders are not clear about their roles and responsibilities this has the potential to adversely impact safety performance. The supervisory arrangements therefore need to make these roles and responsibilities clear.

Training and competence

Supervisors need to be properly selected and, like all personnel on construction sites, they need to be competent. This will involve some level of training. For example the Construction Industry Training Board (CITB) offer a two-day training course for construction site safety supervisors. The training needs to cover both the technical nature of supervision and other skills such as leadership, communication and team working.

Further information can be found on the CITB website.

Checklist for the provision of supervision

Key principles for effective supervision are as follows.

  • The supervisory arrangements in place must be assessed and appraised to ensure that all key supervisory functions are clearly defined and appropriately allocated.

  • The right people for the job must be selected and provided with training where appropriate. Relevant individuals must have the necessary skills and aptitude for supervisory activities, such as planning, communication, delegation and leadership etc; a thorough understanding of local hazards and control measures; and the experience and credibility to gain respect from others.

  • Supervisors must be supported in their roles and responsibilities. Achievable targets should be set and visible support given.

  • Supervisors must be allowed the time and the opportunity to interact with others to fulfill all of their supervisory responsibilities.

  • The performance of supervisors must be measured, audited and reviewed. Supervisors must be supervised.


Lip service is often given to the provision of supervision on site. To be effective, supervision must be methodically and critically considered. Its provision must be planned, managed and monitored. Anything less will see inadequate supervision continue to be a feature of the many accidents that occur on construction sites.