JURY FINDS ELEVATING PLATFORM SUBSTANDARD IN DESIGN
On September 21, 1988, a maintenance worker was painting a flagpole on the front lawn of an elementary school in Mississauga, Ontario. He was sing a portable hydraulic elevating (telescopic) platform to assess the upper portion of the flagpole. The worker was on the platform to access the upper portion of the flagpole. The worker was on the platform near the top of the flagpole when it collapsed. The victim sustained fatal injuries when he struck his head on the school yard pavement.
The site of the accident was secured and preserved by police until a forensic engineering investigation could be performed in anticipation of a Coroners inquest and potential litigation.
At the scene, the elevating platform was found lying on the ground with its mast draped over a parked pickup truck. The mast was almost fully extended when it collapsed.
Four outriggers were found at the scene. An outrigger is a projecting beam which supports the platform in its extended upright position. There were 8 sockets at the base of the machine into which the outriggers could be inserted. Only 3 of the platforms 4 outriggers were attached to the frame when it collapsed. Two of the attached outriggers were improperly located. The fourth outrigger was lying approximately 6 feet away from the lift on the grass. This outrigger was not attached to the machine when it collapsed. The device was clearly labelled with directions on where to place/insert the outriggers. A caution statement was located on the platform. It stated "Consult operators manual before use". Curiously, the operators manual was not found with the equipment, although a plastic transparent tube was affixed to the platform for storing the manual. A danger sticker was also attached to the platform. It stated, "Properly install 4 outriggers. Level unit. All 4 screwjack pads must be on firm surface".
As previously mentioned, only 3 of the outriggers were attached to the base when it collapsed. Two of the attached outriggers were improperly installed. The setup procedure outlined in the operators manual was not followed. The operators manual, which should remain with the platform, was missing. The instruction stickers placed on the frame at the outrigger sockets were not followed. The outrigger screwjack pads were not resting on a firm surface.
The following elements are the basis of a design defect:
The performance requirements of a product are the manufacturers burden, as are the alternatives. This burden consists of the risk/benefit analysis to justify the requirements. It demand comprehensiveness, thoughtfulness, and sensitivity to foreseeable misuse.
There was clearly an element of product misuse in this case. In fact, serious concerns arose as to whether the elevating platform was even appropriate for this job. Nevertheless, because of its implication to this tragic accident, the product was put to the test in order to assess whether or not it was defective.
A Coroners inquest was held. During the inquest, forensic engineering evidence was presented with respect to the previously discussed investigation. This evidence included discussions on alternative designs to prevent misplacement of the outriggers, which are critical to its safe operation, including measures to prevent operation of the unit without all four outriggers properly installed.
The Coroners jury subsequently found the elevating platform substandard in its design and recommended design modifications to prevent the incorrect placement of outriggers.
The findings of the Coroners jury are noteworthy in light of the seemingly comprehensive instructions and warning provided with the equipment. The message to the designers would appear to be that warnings should be considered as a last resort. Once a hazard is identified, the design engineer should design the product to eliminate the hazard. If this cannot be done without affecting the subsequent usefulness of the product or without incurring unreasonable costs, then efforts should be made to guard against that hazard. If this cannot be done without affecting the subsequent usefulness of the product, or it results in an unreasonable cost, then only as a last resort should one warn against the hazard.
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