HSE Alert Warns of Scissor Lift Overturns
Three fatal accidents within a four-year period in Europe involved overturned JLG 500 RTS lifts where a lockout valve failed or the lift/drive interlock system didn’t work, according to the agency, which reminded users to follow two JLG field service bulletins.
Britain's Health and Safety Executive recently issued a Safety Alert to users of JLG 500 RTS and 400 RTS scissor lifts, telling them about its review of three fatal overturn accidents within a four-year period in Europe. In all three cases, the oscillating axle lockout valve failed as the platform was raised and the lift/drive interlock system did not work, which allowed the platform to be elevated above 6.7 meters without the stabilizers being deployed. In at least one of the incidents, the lift was driven with the platform above 6.7 meters, "which should not be possible," according to the agency.
The alert notes that JLG issued two field service bulletins, FSB#2-12-01 in 2002 and FSB#108A3E in 2008, which required owners of affected machines to install a new cam for the lift/drive limit switch. These also told owners of revised inspection procedures for the machines. "It is important that owners of affected machines ensure that these two Field Service Bulletins have been actioned and, if necessary, that their machines have been modified as described in FSB#2-12-01 and that suitable testing and inspection regimes are in place," HSE's alert says.
In two of the three incidents, the axle lockout valve plunger was found to be stuck in the down position as a result of corrosion. In the third incident, the lockout valve switch was stuck and non-operational. "In one of the three overturns, the lift/drive limit switch (part of the interlock system) may have been deliberately defeated, in another the lift/drive interlock system failed for reasons that were not established, and in the third case the roller cam assembly on the limit switch may have been loose," HSE said.
The alert notes daily inspection and function testing are called for the machines' Operation and Safety Manual and reminds users not to operate these or other types of personnel lifts if their safety systems are damaged, overridden, or not working correctly.
On Feb. 14, HSE will begin an intensive one-month inspection campaign focused mainly on fall hazards at smaller British construction sites. Housekeeping and asbestos surveys also will be targeted during this effort, which will end March 11.