This guidance relates primarily to 'cherry pickers'. However, the advice is also relevant to scissor-type MEWPs if the operator is at risk of falling, eg as a result of leaning over the guard rail. The typical MEWP consists of one or more pivoted arms. Movement from a single pivot causes the basket to move through an arc. To make the basket move in an approximately straight line, eg down the face of a building, the operator must adjust more than one control, either simultaneously or alternately.
Many accidents occur when the controls are too 'coarse'.
This may cause the basket to move more rapidly than anticipated or the operator may not be able to compensate sufficiently for the 'arc' movement. The basket then may strike, or be obstructed by, part of the structure, eg a windowsill. 6 Note that MEWPs are intended as work platforms and not as a means of access to elevated levels, eg persons have been injured climbing out of MEWP baskets to get onto a roof. 7 Error of judgement or lack of sufficient instruction and training can cause rapid movement of the basket and collision with racking etc while manoeuvring. Whilst many incidents have been attributed to 'operator-error', many such errors are foreseeable and should be considered as part of a risk assessment.