aerial-work-platform articulating-boom-lift basket-crane boom-lift cage cherry-picker cherrypicker compact danger dangerous elevated elevated-work-platform extension height high hydraladder hydraulic-arm hydraulic-lifting-system hydraulic-platform hydraulics lift looking-up maintenance man-lift manoeuvrable mobile-hydraulic-platform nifty-lifter platform railing rails raised raised-platform safety tall trees up-high work workplatform Harness men men-at-work roof roof-work roofing safety-harness self-propelled workmen