The catapult effect on a mobile elevating work platform (MEWP) occurs when stored energy or an impact to the MEWP’s superstructure causes a whiplash effect, which travels through the boom to the platform.
Obviously, an occupant being ejected from the platform is at severe risk of death or serious injury, even if the MEWP is in the lowered position. An occupant being ejected from the MEWP is also at risk of death or serious injury if catapulted upwards into an overhead obstruction.
Platform occupants and materials can be ejected from the platform, especially if they are not using the correct fall restraint device(s). Any person or object falling from the platform can injure people below.
Vital Risk-Control Measures to observe:
The catapult effect can be prevented if work at height is properly planned and has adequate risk-control measures in place. 3 factors should always be considered:
- Planning the job
- The work environment
- Operation of the MEWP
It is essential that occupants wear personal fall protection equipment (PFPE) connected to the designated anchor point at all times. Occupants must always use a full body harness and an adjustable restraint lanyard, adjusted as short as possible, when using boom-type MEWPs.