It's always been a sticky one this.
Detailing an emergency frequency list.
Comes with working with a mixture of disciplines and about 3000 odd individuals called preppers.
If anyone is brave enough to detail a set, others will disagree.
Hams seem have a set (depending on what day it is and who's in charge)
CB'ers for the past 40 years have used Channel 9.
Mode depends on which country you are in.
Marine VHF Channel 16 156.00 Mhz NFM (That's international)
Air 121.5 Mhz AM or 243 Mhz if you want to upset the military.
And then it gets complicated.
PMR 446. Which one?
Analogue PMR you've got 8 choices
Digital FDMA you've got 16 choices
Digital TMDA you've got 8 choices
PLUS all your CTSS or DCS variants gives you a total of 69 choices.
Go on, be brave, call one, I dare you