Powered access platforms are designed to be strong and stable on a wide range of floors and spaces, on and off site, but tip overs are still the most common type of accident. However, these dangerous and expensive incidents can be avoided as there are two main factors which can prevent MEWP stability problems:
i) knowing how to use the equipment properly and
ii) carefully assessing surface they are used on.
Stabilising the Mobile Elevated Work Platform
MEWPs use various methods to stabilise on uneven ground – some spider lifts have adjustable legs that can be set up in different positions and on different levels, whilst all-terrain vehicles can be set up on severely sloping gradients.
Key points to remember:
• Each machine has benefits and limitations so it is essential to be familiar with the specifics and only operate the machine within the manufacturer’s recommendations.
• Inspect the machinery to make sure it is fit for use and ensure operators are fully trained (this is a legal requirement).
• Look out for the warning lights on the control panel. This will tell the operator if the machine is not level.
• Outriggers generate high pressure at the feet which may not be supported by many areas of soil or unmade ground and even some paved areas, so additional foundations may be required. A site survey and risk assessment will highlight potential MEWP stability problems.
Checking the Ground
Ground conditions have a big impact on the stability of MEWPs and as part of the risk assessment, a ground survey should be completed before every job. Poor conditions may mean further support is required such as spreader plates, timber mats or concrete pads.
Consider these when completing a ground survey:
• The weather has a big impact on outdoor ground conditions, in particular, rain and ground that has thawed after an overnight frost. Regular checks should be made as conditions are changeable.
• Paved areas, such as footpaths, may look strong but could have weaker ground or shallow services underneath.
• Roads in estates and residential areas may be less durable than those designed for commercial vehicles.
• Avoid the edge of trenches and other excavations as these may collapse without warning.
• Indoor spaces should be properly surveyed as floors, cellars and basements are often unable to take the necessary weight.
• Underground services such as sewers, drains, manholes, gas and water mains might be damaged by the weight or could even collapse.
MEWPs can be stabilised and perform safely and effectively on most surfaces and gradients provided a few basic things are taken into consideration. Make sure operatives know how to use the individual machine and what it is capable of. This applies to both road towable and vehicle mounted platforms. Assess the ground conditions to be worked on to ensure the machine can be used to its optimum performance. This will prevent avoidable tip overs or subsidence accidents that can put lives at risk.