Saturday, November 19, 2011


An operative disturbed a section of ducting where he was working. He was unaware that a piece of concrete was on top of the ducting and due to the movement of the ducting, the concrete rolled off. The piece of concrete fell from the ceiling height at approximately 2.5 m and struck the worker on the head, and then thru his shoulder where he sustained a minor injury.
The concrete was identified as the slug from a coring operation from the floor above and was left on top of the ducting after the work was done. Weight of the coring slug is approximately 13-15 kg and having an approximate size of 30 cm long and 10 cm diameter.
This incident could have been more serious if the concerned worker had not been wearing his safety helmet or hard hat as damage to it was substantial.

Root Cause:
  • No clean-up was carried out after the coring operation was done. The coring operative should have ensured that the piece of concrete was located and disposed of.
  • No risk assessment in place for this activity- had there been one the above issue would have been addressed.
  • Lack of proper supervision during the actual operations.
  • Also, "human factors" whereby coring operative forgot to check for the coring slug final location to retrieve or there was deliberate omission of this.

Lessons learned:
  1. All activities should be properly risk assessed. The risk assessment must include hazard and risk to "others" not directly related to the coring activity and control measures included.
  2. Good housekeeping is the first law of accident prevention and should be a primary concern to all supervisors, foremen and the entire workforce.
  3. Safety helmet does protect you in cases like this and almost certainly protected the worker from a serious injury or possibly fatal consequences.
  4. Before each shift, a pre-start briefing should be done by supervisors or work in-charge.