Worker Crushed by Steel Frame Structure

WSH Alert – 1 Jun 2010, Ref: 1011020

Incident

A worker was killed when a steel frame structure weighing more than 250kg toppled and crushed him. The worker was reportedly carrying out welding works on the steel frame structure made with square hollow sections when the incident happened. To facilitate welding works, the worker, together with 3 other workers, manually tilted the frame structure to reposition it on its side. As they were doing so, the frame slipped, toppled and struck the worker. The other 3 workers were unhurt.

Recommendations*

1. Conduct risk assessment: Prior to the start of work, conduct a proper risk assessment to identify all potential hazards and the risks involved. Appropriate action must be taken to eliminate the hazards or to mitigate the risks. Some of the hazards relevant to this incident include:

• Manual manoeuvring and handling of unsupported heavy structure
• Unsafe positioning of workers while manoeuvring the structure
• Castor wheels of the structure not equipped with effective locking devices, or the locking devices not properly engaged while work is being carried out.

2. Establish safe work procedures (SWP): Appropriate control measures and safe work procedures for welding operations, taking into consideration any manual manoeuvring of the structure, must be established, communicated and implemented to ensure the safety and health of the workers involved. As far as is reasonably practical, eliminate the need for workers to manually handle or re-position heavy objects (e.g. employ the use of proper lifting equipment).

3. Proper lifting and supporting system: Implement a proper system to lift, support and maneuver heavy object through the use of appropriate equipment such as chain block with correct load rating or crane to prevent it from collapsing. Metal forks can also be used to prop up structures, and prevent them from toppling during manual positioning operations (see figures 1 and 2 below).

Figure 1: Use of metal fork to prop up metal structures

4. Safe positioning of workers: Workers should position themselves such that they can maintain a firm grip of the object when it is being manoeuvred. This will allow the workers to have continued control and stability when tilting the object during the lowering process. They should also not stand in the path in which the object is being maneuvered, to prevent the object from collapsing onto them.

5. Adequate training and supervision: Workers must be adequately supervised to ensure that assigned tasks are carried out in a safe manner. The responsibilities of supervisors include regular inspections to identify and manage potential hazards at the worksite. For example, for the incident described above, supervisor should ensure that the castor wheels were equipped with the appropriate locking devices and that they are properly engaged prior to moving the structure. The supervisor should also instruct the workers on safe manoeuvring technique for structures with castor wheels. Adequate training of workers is also required to ensure that they can carry out the work properly and safely.

Further Information

1. Workplace Safety and Health Act (Chapter 354A)
2. Workplace Safety and Health (General Provisions) Regulations
3. Workplace Safety and Health (Risk Management) Regulations
4. Singapore Standard CP 92: 2002 – Code of Practice for Manual Handling
5. Canadian Centre for Occupational Health and Safety – Pick Up Tips on How to Lift Safely, please HERE.

* Please note that the information provided is intended to enhance workplace safety and health so that a similar recurrence may be prevented, and is not exhaustive. The information provided should 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.