OA: Orinda Academy
OA: Oxford Academy
OAG: Office of the Attorney General
OAUSD: Old Adobe Union School District
OCESD: Oroville City Elementary School District
OCFA: Orange County Fire Authority
OCHS: Oaks Christian High School
OCHSA: Orange County High School of the Arts
OCMD: Orange County Marshal's Department
OCSD: Orange County Sheriff's Department
OCYSO: Orange County Youth Symphony Orchestra
OESD: Ophir Elementary School District
OFD: OAKLAND FIRE DEPARTMENT
OFD: Oceanside Fire Department
OFD: Ontario Fire Department
OFD: Oroville Fire Department
OGHS: Oak Glen High School
OGHS: Oak Grove High School
OGHS: Orange Glen High School
OGSD: Oak Grove School District
OGUSD: Oak Grove Union School District
OHS: Oakdale High School
OHS: Oakland High School
OHS: Oakmont High School
OHS: Oakwood High School
OHS: Oceana High School
OHS: Oceanside High School
OHS: Olympian High School
OHS: Olympic High School
OHS: Ontario High School
OHS: Orange High School
OHS: Orestimba High School
OHS: Orland High School
OHS: Orosi High School
OHS: Oxnard High School
OJUSD: Oakdale Joint Unified School District
OMSD: Ontario-Montclair School District
OPD: Oakdale Police Department
OPD: Oakland Police Department
OPD: Oceanside Police Department