Skip to main content

CROSS Safety Report

Object rolling into live carriageway

Report ID: 1089 Published: 6 June 2022 Region: CROSS-UK

This report is over 2 years old

Please be aware that it might contain information that is no longer up to date. We keep all reports available for historic reference and as learning aids.


A disc of concrete rolled from a construction area onto a live carriageway, colliding with a passing vehicle.

Key Learning Outcomes

For construction professionals:

  • Acting on concerns and near miss incident reports can ensure work activities are carried out safely

For civil and structural design engineers:

  • Ensure that site specific hazards are clearly communicated to contractors

For contractors and builders:

  • It is good practice to carry out risk assessment and method statement (RAMS) for all construction activities
  • Regular toolbox talks with work crews are a good way of highlighting any risks associated with work activities
  • Create a safety aware culture whereby everyone is looking out for risks and looking out for each other

Full Report

Find out more about the Full Report

This section contains the Full Report submitted to CROSS and describes the reporter’s concerns or experiences. However, the text has been edited for clarity, and identifiable details have been removed to ensure anonymity and confidentiality. If you would like to know more about our secure reporting process, or submit a report yourself, please visit the reporting to CROSS-UK page.


A sub-contractor was preparing a group of bored cast in-situ piles for a new bridge foundation. The operation required excavation of the piling platform to expose the piles, followed by the cropping of the piles into discs to expose the rebar. The discs were then carried away to a spoil heap.

Whilst an excavator was picking up a disc of concrete (pile section), the disc fell off the bucket and started rolling away from the works area. The sloping ground provided enough momentum for the disc to escape the works area and enter the adjacent live carriageway.

A passing vehicle impacted with the roaming section of concrete pile. Fortunately, there were no injuries, but this incident had serious potential for harm and financial loss.

a passing vehicle impacted with the roaming section of concrete pile

The reporter confirmed the underlying causes of the incident:

  • The pile section rolled through a gap in the rigid barrier that enclosed the works area. The gap was a works access that had been temporarily coned off ahead of it being closed with a rigid barrier system.
  • The cropped section of the pile had been cast inside a temporary casing; it was therefore perfectly round allowing it to easily roll.
  • Such an incident was not known to the principal designer, principal contractor, or sub-contractor. Foreseeing, communicating, and mitigating the risk from the outset was therefore not possible.

The reporter considered the lessons to be learned from the incident were:

  • Ensuring that a suitable site enclosure is provided to contain the pile sections. Where works are undertaken next to live traffic, the risk assessments should consider the risk of equipment and materials entering the live carriageway and include appropriate control measures.
  • An excavator with a bucket is not the safest system to pick up circular sections of concrete; they can easily become unstable and mobile. Contractors are advised to review and amend their method statements regarding any pile cropping activities to mitigate against this risk.

Finally, the reporter confirmed that the risk assessment method statements (RAMS) were revised, and further control measures were put in place for the remainder of the work.

This is a stark reminder, continues the reporter, that ‘low probability high consequence’ accidents can still happen no matter how inconceivable they look on paper.

Expert Panel Comments

Find out more about the Expert Panels

Expert Panels comment on the reports we receive. They use their experience to help you understand what can be learned from the reports. If you would like to know more, please visit the CROSS-UK Expert Panels page.

The reporter has provided a good example of the unexpected happening. The required systems were in place to guard against incidents occurring, but the nature of sites is such that it is very difficult to imagine every circumstance that could occur. Nevertheless, good systems of control, planning, training, organisation, risk assessment and method statements together with experienced supervision are proven to reduce incidents to a low level.

This particular incident reminds us that when looking for potential hazards, we should also look outside the site - what are the risks we are creating that will manifest or combine with our neighbour’s activities or hazards. The basis of most incidents is the uncontrolled release of energy - often things falling or moving. If they can fall or move, they will. The questions that then arise are, what harm might they cause, and how with multiple barriers of defence will that be prevented?

This incident reinforces that everybody involved must be watchful and can play a part in preventing incidents. By creating a safety aware culture whereby everyone is looking out for risks, and looking out for each other, we aim to set a high bar in protecting workers and the public from harm. The reporter is applauded for their help in illustrating the unexpected.

a safety aware culture whereby everyone is looking out for risks, and looking out for each other

Submit a report

Your report will make a difference. It will help to create positive change and improve safety.

Our secure and confidential safety reporting system gives professionals the opportunity to share their experiences to help others.