(MEWPS) for tree work - Urban Access

Terrain limitationsMEWPs are designed for working on surfaces that are relatively level, but can sustain a degree ofrough ground such as a building site. The majority of the types of MEWP that have beeninvestigated fall into this category. Some designs are described as having a 4WD capability, whichimplies an application for off-road use. Slope limits are referred to as gradeability in manufacturersmachine data. Manufacturers indicate that some MEWPs, specifically those fitted with outriggers,are capable of working on 30% to 40% slopes. However, considerations such as firmness of theground and potential for slippage due to surface type and weather need to be taken intoconsideration.StabilityCertain types of MEWP have manual or hydraulically operated outriggers. Some machines arefitted with safety devices that will not allow operation of the machine until the MEWP is on a levelbase. Vehicle mounted MEWPs can be fitted with stabilisers to aid stability. Suitability ofstabilisers in respect of ground firmness should be assessed. Where necessary suitable bearers willneed to be placed under stabilisers to maintain stability.ManoeuvrabilityThe manoeuvrability of towed machines can be restricted by the amount of space available. Vehiclemounted MEWPs are also as manoeuvrable as conditions and access and conditions allow. Selfpropelledmachines are highly manoeuvrable. (See section 4.3 Types of MEWPs).Effective reachThis is described as the maximum working length of the boom. Manufacturers’ data identify theworking envelope in a graph form for most machines.Safe working loads (SWL)The SWL is the maximum load that the MEWP will safely carry and includes the weight of alloperatives, tools and equipment that will be in the basket. Some manufactures data may refer to theSWL as platform capacity or lift capacity. All the MEWPs reviewed had SWL notices on thebaskets and they ranged from 120 kg to 340 kg (265 lbs. to 750 lbs.).Health and safetyWhen selecting a MEWP for a particular job, individual MEWP should be evaluated for featuresand operational criteria as they affect health and safety, such as the provision of guarding, hydrauliclocks, heights of steps, communication systems between platform and driver etc.3.3 TYPES OF MEWPMEWPs are supplied in various models, types and sizes. They have been designed primarily for theconstruction and building maintenance industries and adapted to serve other purposes, for exampleindoor surfaces. This section will provide guidance on the type of MEWP that could be used forarboricultural operations.6