In LA, Orange, and San Diego Counties, it's all fire based. In LA/OC if a FD contracts with a private company for transport, it's only a BLS ambulance showing up while the paramedics are firefighters. San Diego is either all fire, or they'll contract with AMR or Rural/Metro, and they'll have a fire medic, and a private medic on the ambulance, I think whoever gets there first is the medic in charge, and Riverside and San Bernardino Counties are similar with FD paramedic response to all medical calls and an AMR paramedic ambulance as well, but I'm MUCH more fuzzy on the Inland Empire county's way of doing things, so someone correct me if I'm wrong lol