Only trained people may operate one
OSHA requires that only authorised, trained persons operate an aerial lift. Training has to cover the specific type of machine. A scissor lift briefing does not qualify someone on a boom lift, because the controls, the stability envelope and the fall protection rules are all different.
The training obligation sits with the employer, not the rental company. Renting a machine does not transfer it, and a delivery driver walking someone round the controls for ten minutes is not training in the sense the standard means.
Fall protection: the rule differs by machine
On a boom lift, a full-body harness with a lanyard attached to the manufacturer's anchor point is required. The reason is catapult risk: a boom platform can be thrown clear by a sudden movement or an impact, and the guardrail will not stop that.
On a scissor lift with the guardrails up and the gate closed, the guardrails ARE the fall protection and a harness is generally not required. This is the single most confused point on any jobsite, and it is worth stating plainly to a crew because people routinely apply the boom rule to a scissor lift and the scissor rule to a boom.
Belting off to an adjacent structure from inside the basket is specifically prohibited. If the machine moves, the occupant does not.
Inspect before every shift
A pre-start inspection covers the controls at ground level and at the platform, the emergency lowering system, guardrails and gate, tires, hydraulic leaks, and the decals and load chart. It takes a few minutes and it is the thing an inspector will ask for records of.
Do not modify a machine, and do not exceed the rated load, which includes the occupants, their tools and anything hanging off the rail.
The ANSI A92 layer on top
The current ANSI/SAIA A92 suite adds requirements OSHA does not spell out: a written risk assessment for the task, a site survey before the machine is used, supervisor training as a distinct category from operator training, and a rescue plan for getting someone out of a stranded platform.
These are the manufacturer's and the user's obligations, and they are increasingly what a general contractor asks to see before a machine goes to work on their site.