Working height is the number most people check first when comparing elevated work platforms. Reach — the horizontal outreach — is the number that actually determines whether the machine can do the job from where you park it. Understanding the difference saves time, prevents repositioning delays, and occasionally saves a job that would otherwise need a different machine.
What horizontal reach means
Horizontal reach is the maximum horizontal distance from the machine's rotation axis to the centre of the platform basket, measured when the boom is elevated. It tells you how far out from the vehicle the platform can be positioned at working height — not how far out at ground level.
Reach and working height are linked. A machine typically achieves its maximum horizontal reach at a mid-range elevation angle, not at full height. At maximum height, the boom is usually closer to vertical, which reduces the horizontal distance significantly. Manufacturers publish the reach figure at the most favourable combination of elevation and boom extension — always confirm both figures when planning a specific job.
Reach vs working height: the key difference
Working height describes how high up the platform can go. Reach describes how far out it can go. Both matter, and they are rarely maximised at the same position.
A machine with 16m working height and 8m reach can position the platform 8m out from the truck at some elevation — but not necessarily at 16m height. If your work point is 12m up and 7m horizontally from where you can park the truck, both numbers must be confirmed against the machine's envelope diagram, not just the headline specifications.
Why reach matters on site
Reach determines whether you can access a work point without repositioning the truck. On confined sites — narrow streets, gated industrial yards, busy car parks — repositioning can be impractical or impossible once work has started.
For overhead line work, reach also determines how close the basket comes to live conductors. The required electrical exclusion zone must be maintained between the basket (including the operator and any tools) and any energised line, so the machine's outreach directly affects safe positioning.
On tree work and vegetation management, greater reach means fewer tree climbs and less repositioning. On building façade work, reach determines how far along a wall the machine can cover from each set-up point.
How to use reach in planning
Before confirming a machine for a job:
- Identify the work point — its height and horizontal distance from the nearest safe truck position.
- Confirm both the working height and horizontal reach from the manufacturer's envelope diagram for that machine.
- Allow margin: always plan with some reach in reserve so the operator is not working at the extreme of the machine's envelope.
- Account for outriggers: the truck's outriggers extend the footprint, which may affect how close you can park to a wall or edge.
- Check the site for ground conditions, overhead obstructions, and exclusion zones before arrival.
This guide is general information prepared by EWP Australia and is grounded in publicly available Australian Standards and Safe Work Australia material. It is not a substitute for the current published edition of the relevant standard or for site-specific engineering advice. Always work from the current standard and consult a competent person for your specific equipment and application.