Wednesday, June 9, 2010

Worker Crushed by Toppled Pipe - WSH Bulletin & WSH Council

9 Jun 2010


In this incident, a worker was using a hand held power tool to grind/polish a welded joint on Pipe A within a pipe bridge. He was working in a 300mm gap between Pipe A and Pipe B, when Pipe B suddenly rolled towards Pipe A. The toppled Pipe B crushed and killed the worker.

Both pipes were about 300mm in diameter and weighed several tonnes. Each pipe was welded with supporting shoes at interval spacing of about 6m and rested on supporting I-beams. At various shoe locations on Pipe B, two brackets were welded to the I-beam to hold the shoe in place, and restrict the lateral movement of the pipe. The shoes were not permanently fixed to the I-beams to allow for longitudinal movements due to thermal expansion and contraction. At some of the shoe locations, timber blocks were also placed between the lateral restraining brackets. As the height of the timber blocks exceeded the height of the brackets, the pipe shoes were resting on the timber blocks and not secured by the brackets.

Figure 1. Pipe B toppled and crushed the worker.


1. Conduct risk assessment: Risk assessment must be carried out before starting any work. Through risk assessment, employers and employees can identify potential hazards and take appropriate actions to eliminate or reduce the risks involved. Control measures and safe work procedures must be established, communicated and implemented to ensure the safety and health of the employees involved. Risk assessment should also cover non-routine or emergency situations, so that measures can be planned for such situations. Potential hazards for this incident include:

- Unstable placement of pipes on timber blocks.
- Unsecured pipe that is not braced against toppling.

2. Implement Safety and Health Management System: It is important for the Management to put in place an effective workplace safety and health management programme to guide the establishment of a safety management system and proper work procedures. Some of the elements in a WSH Management Programme include:

- Risk management - As explained, proper risk assessment should be conducted to identify hazards and mitigate risks

- Safe work procedures - Establish safe work procedures for carrying out the task safely. Ensure proper supervision and implementation of the safe work procedures for the task. Supervisors should provide direct and close supervision of the tasks performed by the workers under their charge

- Safety training – All workers should be adequately trained in order for them to perform their work competently. They should also be properly briefed so that they are aware of the safety and health issues.

- Communication of safety and health issues – The safety management plans and work procedures should be clearly communicated to all supervisors and workers (e.g. at the daily toolbox meetings)

2. Secure pipes: Ensure that safety measures are in place. Pipes should be adequately secured, or restrained from uncontrolled movement, e.g. with the use of chain blocks before the start of any work.

3. Ensure effective communication channels: The occupier should put in place a good and effective communication system. This is to ensure that the different contractors are regularly updated and aware of the progress of on-going works and safety issues around the worksite, e.g. checking whether the adjacent pipes have been fully installed before commencing grinding / polishing work.

Further Information

1. Workplace Safety and Health Act, please click here.
2. Workplace Safety and Health (General Provisions) Regulations, please click here. 3. Workplace Safety and Health (Risk Management) Regulations, please click here.
4. Workplace Safety and Health (Safety and Health Management System and Auditing) Regulations 2009
5. SS 506 : Part 1 : 2004 - Occupational safety and health (OHS) management system – Specification

*Please note that the information provided is not exhaustive and for the benefit of enhancing workplace safety and health so that a similar recurrence may be prevented. The information provided is not to be construed as implying any liability to any party nor should it be taken to encapsulate all the responsibilities and obligations of the reader of WSH Alert under the law.

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