In the new Spread the Load campaign, IPAF is recommending that spreader plates should always be used with boom-type elevating work platforms when fully supported on their outriggers. How should this guidance be implemented on sites? We ask a panel of industry experts for their views
Spreadingthe word S
preader plates are, as their name suggests, a way of reducing the load imposed by an outrigger or
stabiliser leg, by spreading the ground bearing force as the outrigger supports the weight of the machine. A typical 18m boom can weigh more than
10 tonnes and can generate a ground- bearing pressure exceeding 14.06kg/cm2
That is more than 12 times the pressure of a human foot, so digging a heel into the surface to see if has suffi cient strength to support the weight is hardly good enough. By spreading that load through a larger
area you reduce the point load on the ground, cutting the risk of the outrigger sinking into the material below and the machine becoming unstable. Because of the way in which force is calculated, even if the spreader plate is just twice the size of the outrigger foot, it will reduce the ground pressure by a factor of four.