Assuming you have checked out the database:
All fire radios have the same basic layout:
All talkgroups have a zone number and letter.
Zone 1 is local agency TG's 1A-1C + PD or other TG's as determined by agency.
Zone 2 is Metronet North cities
Zone 3 is Metronet Central cities and OCFA Batt 9 (Santa Ana) - this would include HB on 3G
Zone 4 is OCFA North, mainly
Zone 5 is OCFA South + Laguna Beach (San Clemente is on 5E)
Zone 6 is Med Talkgroups
Zone 7 is misc mutual aid/small coverage area TG's
Zone 8 is PIO
Zone 9 is TAN (Mut aid)TG's as shown in the info at the top of the DB page
Zone 10 TAN (Mut aid) conventional
Zone 11 AIRTAC
Zone 12 ICALL/ITAC
Zone 13 ICALL/ITAC local repeaters
Zone 14 FIREMARS/Talkaround