Fatality Assessment and Control Evaluation (FACE) Program |
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Welder Falls from Boom Forklift Platform When Boom Shifts Laterally |
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Summary
At one point, the men were adjusting the lateral position of the raised platform using the frametilt function (sway control) of the forklift. While moving the platform to the right, the victim yelled, "Stop", however the boom and the platform kept moving to the far right position and the victim fell off the unprotected left end of the platform, landing on the metal catwalk 20 ft. below him. The man was not wearing any sort of harness or safety line, nor was he wearing a hard hat. He sustained fatal head injuries and was dead at the scene when firefighters arrived. At that time the boom for the forklift was situated to the far right position with the left front wheel of the machine raised two feet off the ground (see Photo 1). Recommendations based on our investigation are as follows:
IntroductionDuring the spring of 2003, a 39-year-old welder died after falling from an aerial work platform attached to a forklift truck. The Iowa FACE program was notified of this incident the next day from the State Medical Examiner, and began an investigation. Additional information was gathered from newspapers, the forklift manufacturer, OSHA, and the county Sheriff, who also provided excellent photographs of the scene. The employer was a metal fabricator from the local community. Two employees and the owner of the company were working at that location, the victim working on the personnel platform as a welder. Other details about this victim, and his company's safety program or written policies are unknown, as the company owner was unwilling to discuss this incident further with investigators.
Back to TopInvestigationThe 3-man work crew was building a new catwalk and ladder assembly on the side of a cement silo, and the victim was working on a personnel platform as a welder. Also on the platform were a wire welder, a metal chop saw, some welding hand tools, and a welding mask. The work platform was made of steel with a plywood base, and was approximately 4 x 12 ft. in size. It was constructed with seven removable metal guardrail sections, two of which were missing from the corner adjacent to the silo where the victim was working (see Photo 4). Welded to the bottom of the platform were two 8-ft. long steel channels, which were made to receive the forks of the boom forklift truck (see Photo 5). It is not known how the extended channels were attached to the original forks of the machine. The boom forklift was routinely used in this manner for fabrication and assembly of various outdoor metal projects.
A rough terrain boom forklift of this type is also called a telescopic handler by some manufacturers. It is designed to raise and extend loads in a single vertical plane, and does not provide for lateral movements of the boom, as is seen on larger truck-mounted cranes. These machines usually have built-in sway control, which is a method to level or tilt the frame of the machine if it is situated or traveling on ground that is sloping to the left or right. The axles of the machine are equipped with hydraulic cylinders, which the operator can actuate to shift the frame back to level before a lift is initiated. In the operator's manual for this machine, the control for this is called the carriage tilt lever. From photographs it is obvious the work platform is tilted far from the silo. The workers were accustomed to using the sway control feature of the machine to make minor lateral adjustments while personnel were on the platform. This was thought to be a very common procedure that many local construction crews did, and was not perceived as a dangerous action, although it is specifically forbidden in the operator's manual for this forklift. The owner of this company was familiar with lighter-duty man lifts, but preferred this modified forklift for several reasons. Man lifts are designed to lift personnel with minimal tools and materials, but these machines were thought to be inherently lighter and less stable than the modified forklift, and they provided no means for lateral adjustments, nor did they provide space or lift capacity for tools like a welder, chop saw, angle irons, etc. On the day of this incident, the crew was using the boom forklift in a fully raised and extended position, which placed the platform approximately 35-40 feet off the ground. They were adjusting the personnel platform slightly to the right (from the operator's position) when the victim yelled to the operator to "Stop". The boom kept moving to the extreme right position, however, and the victim apparently lost his balance and fell off the unprotected end of the platform. He was not wearing any sort of fall-protection safety gear, lifeline, or harness, and was not wearing a hart hat. The man fell to the existing metal catwalk about 20 feet below, where his co-worker was located. The welder received fatal head injuries and died at the scene. The operator of the forklift immediately called 911, but when rescue crews arrived, the victim was obviously dead at the scene and resuscitation was not attempted. The left front wheel of the forklift raised two feet off the ground when the boom shifted to the far right position. It is unknown if the boom was stuck in this position, or why the boom was left in this position when firefighters arrived. The operator's manual from this manufacturer specifically warns against creating a custom work platform for personnel and attaching it to the forklift. However, over the last 10 years, this has become a common and accepted practice for many construction companies, and ASME gives detailed outlines in their standards (ASME B56.6-1992). The company in this case was cited by OSHA for failure to provide proper training to its employees regarding the specific hazards encountered at this worksite, and for failure to provide specific safety equipment necessary for employees, especially the victim working on the elevated platform. The owner did not get permission from the forklift manufacturer before constructing the work platform, nor before he attached the extended personnel platform to the forks of his machine. Back to TopCause of DeathThe cause of death as listed on the Medical Examiner's report was, "multiple blunt force injuries of the head and neck". Back to TopRecommendations/DiscussionRecommendation #1: Operators of rough terrain forklifts should never use the sway control feature of the machine to make lateral adjustments of a raised load.Discussion: The approved use of the boom on this machine was strictly in an up and down motion, and there was no provision for lateral movements or rotation, which are possible on many larger truck-mounted cranes. One must back up and reposition the forklift if a lateral position is desired, even for a few inches. Normally, the frame-tilt (sway control) function of the forklift is used only for leveling the machine while traveling along sloping ground or making a lift on terrain that is slightly sloped to the right or left. The operator's manual for this machine forbids traveling on slopes of greater than 16.5 degrees (left or right), and forbids placing or retrieving a load on slopes greater than 4.5 degrees (left or right). With the boom in a full vertical position, it is possible to make minor left and right shifts of the boom and the forks using the sway control feature. The owner's manual for the forklift specifically warns against this practice, for obvious reasons of creating an off-balance load, losing the load, or tipping over of the machine. However, while using a relatively light-weight work platform, workers are tempted to make minor left and right adjustments with the hydraulic frame-tilt control. In this case, the platform was moved to the far right position when the sway control was used, causing the victim to lose his balance on the platform and fall off. All forklift loads should be leveled before the lift is initiated, or before the boom is extended, and this especially applies to personnel platforms. It is never a good idea to use the sway control to make lateral adjustments while workers are on an extended and raised work platform. Small adjustments in the hydraulics of the sway control cylinders produce exaggerated movements of the forks if the boom is extended. If the sway control lever is rapidly pushed to one side, it will cause violent and jerky movements of the personnel platform if it is raised high off the ground.
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