Download the free SJCEMSA ALS Treatment Protocols App for Android or iOS devices.


If you have comments or feedback on our web site, we want to hear from you!
Submit feedback >>



On this page:

System Coordinators
OES Region IV Multi-casualty Plan


When disaster strikes, local medical and health resources may be inadequate to meet the demand. The Medical/Health Mutual Aid System is designed to address this issue by facilitating the distribution of regional, state, and/or federal resources to the area(s) in need.

In California the Medical/Health Mutual Aid System is facilitated by grouping counties, referred to as Operational Areas, together to form six Mutual Aid Regions. Within a region, if disaster strikes, resources are distributed from the unaffected Operational Areas to the affected one.

San Joaquin County is part of Region IV. Other counties in Region IV include Alpine, Amador, Calaveras, El Dorado, Nevada, Placer, Sacramento, Stanislaus, Tuolumne, and Yolo.

View a detail map of Region IV >> Updated August 2015 (Designed to print 42" x 36")

View a map showing the six Mutual Aid Regions >>

California Public Health and Medical Emergency Operations Manual (EOM) July 2011 PDF Document

View training for California Public Health and Medical Emergency Operations Manual >>


Medical Health Operational Area Coordinator (MHOAC)
An individual appointed by a county Department of Health Director/Local Health Officer who is responsible in the event of a disaster or major incident where mutual aid is requested, for obtaining and coordinating services and allocation of resources within the Operational Area (county).

Regional Disaster Medical Health Coordinator (RDMHC)
A volunteer local health officer, EMS agency medical director or EMS agency administrator jointly appointed by the Directors of the California Department of Health Services (DHS) and the Emergency Medical Services Authority (EMSA) based upon the recommendation of the local health officer for a mutual aid region. The role of the RDMHC is to plan for and coordinate medical and health resources within one of California's six mutual aid regions during times of disaster or other major event requiring medical or health mutual aid.

Regional Disaster Medical Health Specialist (RDMHS)
An individual selected by a local EMS agency, under contract with EMSA, as a staff function to coordinate preparedness activities, and to assist the RDMHC in coordinating services in the event of a disaster or in the event that medical mutual aid of some type is requested.

Click here to see a diagram that illustrates how the System Coordinators orchestrate the Medical/Health Mutual Aid process.


RDMHC Policy # Title Effective Date
08-001    Regional Polling of Hospital Inpatient Beds 10/01/2008
16-001 Receiving Hospital Status 01/01/2016


The current OES Region IV Multi-Casualty (MCI) Plan is comprised of 3 interdependent manuals: Manual I - Multi-Casualty Incident Field Operations; Manual II - Multi-Casualty Incident Control Facility Operations; and Manual III - Medical/Health Mutual Aid System.

The Adobe Acrobat Reader is needed to view and print the documents below. If you experience difficulty viewing the following documents you may download the Adobe Acrobat Reader for free from the Adobe web site.

Title Revision Date
Manual 1 - Multi-Casualty Incident Field Operations (PDF) June 1998
Manual 2 - Multi-Casualty Incident Control Facility Operations (PDF) February 1998
Manual 3 - Medical/Health Mutual Aid System (PDF) March 2005


The San Joaquin County Administers EMResource for the Region. The following documents have been developed to assist with just-in-time training and user development.