Aerial Lift Types, Components, and Selection
Choosing the right machine is a scored decision, not a preference: the exam gives a task and expects you to match platform geometry, capacity, terrain, and power source to it.
Two classification axes
ANSI/SAIA A92.20 classifies MEWPs by Group and Type.
- Group A - platform stays within the tipping lines (scissor lifts, vertical mast lifts). Load is essentially vertical; more platform area and capacity.
- Group B - platform extends beyond the tipping lines (boom lifts). Reach over obstacles, but watch overloading and side loads.
- Type 1 - travel only with the platform stowed.
- Type 2 / Type 3 - travel with the platform elevated, only within manufacturer limits on firm, level surfaces.
Bucket trucks are not MEWPs; they are vehicle-mounted elevating and rotating aerial devices under A92.2, mounted on a chassis with stabilizers and, for line work, an insulated boom with a current dielectric test.
Matching machine to job
Ask: what working height and horizontal reach? Working height is roughly platform height plus 6 ft (2 m) for a person. Then capacity (occupants plus tools), floor loading, indoor emissions, door widths, transport weight, wind exposure, and whether the ground is slab, lawn, or fill.
Worked example
Hang a 4 ft × 8 ft banner at 30 ft on a flat concrete wall inside a warehouse, two workers, 150 lb of tools. 30 ft working height means about a 24 ft platform. A 26 ft electric scissor lift delivers the capacity, zero emissions, and a level slab floor, and its footprint fits the aisle. If racking blocked the approach, an articulating boom would substitute - at the cost of reach-through and capacity.
Traps
- Confusing platform height with working height and arriving short.
- Defaulting to a boom lift where a scissor is safer and cheaper.
- Ignoring wind and side-load limits when the platform carries a panel.