49 CFR §804.8

1. (a)The time or place of a meeting may be changed following the public announcement only if the NTSB publicly announces such change at the earliest practicable time. Members need not approve such change.
2. (b)The subject matter of a meeting or the determination of the Board to open or to close a meeting, or a portion thereof, to the public may be changed following public announcement only if:
   1. (1)A majority of all Members determines by recorded vote that NTSB business so requires and that no earlier announcement of the change was possible; and
   2. (2)The NTSB publicly announces such change and the vote of each Member thereon at the earliest practicable time.