Access Equipment types - continued

A boom, or occasionally a scissor-lift, mounted on the back of a truck or van, that can be driven on the roads and used for highways work. Almost all have to put down supporting jacks to stabilise the suspension before elevating the boom.

A boom where the turret is substantially contained inside the enclosed vehicle. The extra weight of the van body can mean that the maximum reach is restricted to only 12 - 15 metres.

The turret of the boom is mounted on top of a flat-bed lorry chassis. This is lighter and allows more reach as a longer boom is possible, with more articulations. CherryGreen's truck mounted boom can do under-bridge work because of the way it is designed and 'nests' on the vehicle. Our truck mount is small enough to access anywhere a van can go, but can reach much further outwards and upwards.

This describes the number of joints in the boom which give the machine its flexibility. Generally more articulated means more versatility, but there is trade-off with weight and height. More articulated booms tend to be slightly shorter than straight telescopic booms.

To get the length required, different sections of the boom slide inside each other. This is a light way of getting most height, but a purely straight telescopic boom is only suitable for some applications - there is no 'up and over' capability and the machine or vehicle has to be in straight line of sight with the target workplace - this isn't always possible. Many booms involve a mix of telescopic and articulated sections to give maximum flexibility and reach.

A hinged extension to the top of the boom that opens out at height to enable access at unusual angles - this can be 'up and over' a roof, wall or hedge.

Normally a platform that moves itself on wheels or tracks. Some can be driven along by the operator while in the cage, sometimes at full height. Some have 4-wheel drive capability, and some have large wheels for rough terrain. Most weigh between 6 and 11 tonnes, depending on how high the boom can go. Most have a large, heavy rotating turret that counter-balances the weight of the extended boom. SPB's are normally delivered to site by a heavy goods vehicle or trailer.