When using a small UA in a commercial operation, who is responsible for briefing the participants on emergency procedures?

Why →The remote PIC is responsible for the safety of the entire operation, including ensuring that all participants (visual observers, crew members, clients in the immediate area) understand their roles and emergency procedures. This responsibility flows from the remote PIC's duty of safety under § 107.19.

The trap →The owner may not even be present at the flight. The visual observer assists with flight safety but does not bear responsibility for briefing others. All crew responsibilities trace back to the remote PIC.

Field note →Develop a standard briefing card for your commercial operations: emergency abort signal, where to stand during operations, what to do if the aircraft malfunctions, and when to call 911. A 2-minute briefing before each job establishes professional credibility and reduces liability.