Issued: 25 January 2012
Last Updated: 25 January 2012
The purpose of this alert is to highlight the importance of safe systems of work when performing maintenance on plant, following a fatality that occurred when a worker was replacing parts on a vehicle lifting device.
A worker was killed when he was crushed by the lifting device while replacing one of the scissor lift arms. The incident involved a scheduled manufacturer warranty recall on a vehicle lifting device.
Photograph 1 - lifting device similar to the one involved in the fatality.
It should be noted that in this incident, the design of the device was not shown to be deficient - rather the system of work used at the time of incident was unsafe.
One of the scissor lift arms on the unit was being replaced as required by the manufacturer. The supplier of the vehicle lifting device was engaged to carry out the remedial work on the unit.
The lifting device itself had been designed to accommodate purpose built post stands for supporting and securing the unit's platform deck into position, so that the under chassis scissor arm and hydraulic ram components could be disconnected. However, the two workers carrying out that task did not use the post stands while performing work under the platform.
Instead of using the recommended safe system of work, the workers used two makeshift props under one end of the platform deck, along with a hydraulic jack under the opposite end of that deck to support the platform. While attempting to align and fit one of the connection pins into the newly fitted scissor arm, the platform deck became unstable and one of the support props dislodged. This caused the platform deck to crash to the ground, tragically crushing one of the workers between the scissor arm action and the frame.
An investigation of the incident revealed the following:
- The manufacturer provided the supplier with information explaining the procedure to follow when replacing the scissor arm. The procedure specified the use of three purpose built post stands made by the manufacturer, to support the platform deck, through brackets that are securely attached to that deck.
- The two makeshift props and hydraulic jack used to support the platform were not restrained or clamped to prevent lateral movement.
- The employer of the workers did not ensure, either by way of instruction, training or supervision, that the workers were aware of, or followed, the procedure as recommended by the manufacturer.
Plant that supports vehicles must:
- be used/designed to ensure structural integrity and stability
- be fitted with an additional back up safety system which must be engaged prior to commencing work underneath the plant. For example use of vehicle axle stands (once vehicle raised from ground).
Prior to commencing work consider the following:
- Have the hazards/risks been identified?
- Have the risks been assessed?
- Have all appropriate controls been considered and implemented?
- Have the manufacturer's instructions on the use or maintenance of the plant been considered and implemented?
- Have those involved in the work received all the instruction and training required to perform the work safely?
The Work Health and Safety Act 2011 imposes health and safety obligations on a person(s) conducting a business or undertaking, whether as an employer, self-employed person, designer, manufacturer, supplier or owner of plant.
Further information may be obtained from the following codes: