(a) Except as provided in paragraph (b) of this section, no person may
operate an airplane carrying passengers unless it is equipped with signs
that are visible to passengers and flight attendants to notify them when
smoking is prohibited and when safety belts must be fastened. The signs
must be so constructed that the crew can turn them on and off. They must
be turned on during airplane movement on the surface, for each takeoff,
for each landing, and when otherwise considered to be necessary by the
pilot in command.
(b) The pilot in command of an airplane that is not required, in
accordance with applicable aircraft and equipment requirements of this
chapter, to be equipped as provided in paragraph (a) of this section shall
ensure that the passengers are notified orally each time that it is
necessary to fasten their safety belts and when smoking is prohibited.
(c) If passenger information signs are installed, no passenger or
crewmember may smoke while any "no smoking" sign is lighted nor may any
passenger or crewmember smoke in any lavatory.
(d) Each passenger required by §91.107(a)(3) to occupy a seat or berth
shall fasten his or her safety belt about him or her and keep it fastened
while any "fasten seat belt" sign is lighted.
(e) Each passenger shall comply with instructions given him or her by
crewmembers regarding compliance with paragraphs (b), (c), and (d) of this