Passenger information requirements, smoking prohibitions, and additional seat belt requirements

This regulation establishes requirements for passenger information signs and smoking prohibitions on Part 121 airline flights.

Aircraft must have illuminated "Fasten Seat Belt" signs that turn on during all ground movement, takeoffs, landings, and whenever the pilot deems necessary. Passengers must keep their seat belts fastened when this sign is lit. Additionally, "Fasten Seat Belt While Seated" signs or placards must be visible from every passenger seat.

Smoking is prohibited throughout the aircraft, including all lavatories. "No Smoking" signs must be illuminated or placards posted for the entire flight. Each lavatory must display a warning about the $2,000 penalty for tampering with smoke detectors.

Very limited exceptions allow flight deck smoking (only if physically separated from passengers) on certain supplemental or intrastate operations, but never during ground movement, takeoff, or landing.

Older nontransport category aircraft have alternative compliance options using placards and oral crew instructions instead of illuminated signs.

*This is a plain-English summary for study only. The official 14 CFR text on this page is controlling — always read the current regulation and consult a CFI.*