Emergency Medical Services (EMS) Agency

Radio Communication


Kim Buard, Communication Coordinator
(562) 378-1629 (office)
(213) 216-2085 (cell)

CountyWide Integrated Radio System (CWIRS) – LA County Departments only


The County of Los Angeles operates an 800 MHz, trunked, simulcast radio system. With the exception of the county fire department and the Sheriff, all county departments participate. To communicate with Fire and Sheriff, there exists a bridging interface. In the event of a declared emergency Los Angeles County departments can communicate with each other and free up the other communication channels.

Emergency Medical Services coordinates CWIRS for the Department of Health Services. In addition to training on the use of the radio, EMS coordinates maintenance and repair of all end user equipment and maintains an inventory of all issued radios. EMS conducts a bi-annual inventory of all CWIRS Radios. Everyone who is issued a portable radio and Facility Representatives who oversee the hospital base radios must complete a Radio Inventory Form. Facilities must also update the CWIRS Directory each time a radio changes hands. Failure to update the biannual inventory may cause disruption of service and a reactivation fee.

On the second Thursday of each month EMS conducts a CWIRS roll call of selected Department of Health Service radios. The goal of the test are to:

  • Test the radios at Emergency Medical Services Headquarters.
  • Verify end user radio equipment.
  • Validate that the users know how to use their radios.
  • Provide end users radio “air” time.

Additional Information

CWIRS End User Training Manual 2015
CWIRS Inventory Form
CWIRS Directory by Last Name
CWIRS Directory by Assignment
CWIRS Directory by LID


  • Administration and coordination of the medical channels for the Paramedic Communication System (PCS)
  • Department of Health Services coordination of the County Wide Integrated Radio System
  • In Partnership with the Los Angeles County Internal Services Department (ISD) maintain the Hospital Emergency Administration Radio (155.340 MHz, HEAR, VMED 28) remote sites
  • Telecommunication Management (telephones, cell phones, pagers and air cards)
  • Technology Support for Ambulance Services Computer Aided Dispatch System.

Paramedic Communications Systems (PCS)


Currently pre hospital on-line medical control is provided by 20 acute care hospitals. Two (2) of these hospitals are operated by the Department of Health Services (DHS). Staff providing on-line medical control is employed by the hospitals under the direction of the Pre-hospital Care Coordinator (nurse) and a Medical Director (physician). In calendar year 2011, the base hospitals handled 236,000 contacts. In addition to field medical control, the hospital staff is also responsible for continuing medical education and quality assurance.

The communication equipment used for medical control is purchased, installed and maintained by the participating hospitals. Except for a few exceptions all hospitals are assigned a primary communication channel and a back up. In addition, hospitals provide a minimum of two telephone lines to be used for paramedic access. Due to the Los Angeles topography some hospitals must maintain remote radio sites to provide communication to some outlying field units. These remote sites are connected to the base hospital using leased lines, leased by the base hospitals.

Los Angeles County maintains a network of high remote radio sites that are available to extend local hospital communications when necessary. The county‘s back haul circuits (i.e. fiber, microwave) interfaces with the hospital lease lines at local county buildings. The county remote radio sites along with the circuits are maintained by the Los Angeles County Internal Services Department (ISD).

Narrow Banding

On November 19, 2012, EMS completed the migration of all the Medical Channels at the remote radios sites and County Operated Hospitals from wide band to narrow band. The channel previously called Med 9 is now called Med 10. The frequency pairs (462.975/467.975) and CTCSS tone of 203.5 remain the same.

For more information please contact  (562) 347-1629


Los Angeles County EMS has been an active participant in interoperability planning for many years as members of the executive and technical committees of the Los Angeles Regional Tactical Radio System LARTCS and the Los Angeles Regional Interoperability Communication System LARICS. EMS intends to migrate the paramedic communication system into LARICS when the system becomes operational.

Additional Information

Base Hospital Directory
Remote Radio Sites Map
Medical Channel Protocols
Medical Channel Assignments
Paramedic Communications Policy 716

VMED28 (Formerly HEAR)

The original purpose for this system was to provide voice communication to hospital administrative staff. It was meant as a tool to be used only during emergencies. Over the years with the increased stress caused by hospital closures and emergency department overcrowding, the use of VMED28 was expanded to include notification to field units as to the availability of the emergency departments. As other medical communication needs were identified the use of VMED28 was the natural solution.

The medical band that includes VMED28 (155.340.156.7) is available for licensing nationwide for use by medical personnel. For this reason LACOEMS has designated VMED28 as their interoperability voice channel for incoming medical resources.

Using 12 remote transceivers in selected high elevation radio sites and a automatic voter VMED28 Remote sites Map, EMS has expanded coverage of VMED28 to the majority of Los Angeles County. There still exist some canyons and shadow areas that due to sparse population would be cost prohibitive to attempt to cover.

The key to effective communication using VMED28 is the Medical Alert Center (MAC). MAC, a 24/7 communication center operated by LACOEMS, provides communication monitoring, provides relay information to hospitals, and would be the primary notification center for any events requiring medical resources outside the normal operating channels. Along with the Central Dispatch Office (CDO) MAC is part of the Coordinated Communications Center for the Department of Health Services.

In addition to building out the VHF channel by installing remote transceivers at strategic “high” sites”, LACOEMS participates in the Los Angeles Regional Tactical Communication System LARTCS as a means to provide medical communications to agencies who do not maintain VMED28.

Narrow Banding

On November 19, 2012, EMS completed the migration of all VMED28 remote radios sites and County Operated Hospitals from wide band to narrow band and changed the designation, Hospital Emergency Administrative Radio (HEAR) to VMED28. This step is being taken in order to comply with the Association of Public Safety Communication Officers (APCO) and the National Public Safety Telecommunications Council (NPSTC) Standard Channel Nomenclature for the Public Safety Interoperability Channels. THERE WILL BE NO CHANGE IN OPERATIONS.

For more information please contact (562) 378-1629