Until the early 1970's, most ambulances were operated by the funeral homes in Texas. Communications consisted of the funeral home receiving a telephone call from the local law enforcement agency. If this law enforcement agency allowed it, the ambulance had a radio on the police frequency (usually 37.180 or 37.260), which they used while responding and transporting the patient to the hospital or to the funeral home. At this point, there were no medical control links and the hospital usually did not know a patient was en route until the ambulance arrived and rang the door bell. In the late 1960's and the early 1970's, funeral home ambulance services were being taken over by cities, counties, private, and volunteer EMS providers. The result of this movement was improved patient care and communications capabilities through the use of VHF high band frequencies. Ambulance companies dispatched and operated on 155.340 while ambulances communicated with hospitals on 155.280. Gradually the larger agencies and cities began to license their own frequencies. In 1970, the Texas Department of Health formed a communications section to promote EMS communications needs. This agency used federal grant money to start building communications systems across the state. This has evolved into an area of technical assistance for agencies improving or evaluating their communication needs and abilities.
In the mid 1970's, agencies that could afford to, began to upgrade to the UHF frequency band due to the noise level as well as the interference on the VHF frequencies. The result of this move was that rural providers suddenly could no longer communicate with these agencies. In the late 1970's, telemetry was introduced to EMS. This allowed for the EMS personnel to send vital signs as well as EKG information directly to the hospital over the radio. With limited frequency availability, frequency assignment became congested, especially in the major metropolitan areas of Texas.
As communications became more congested in the UHF range, and more sophisticated equipment became available, the agencies and cities with the resources again began to upgrade equipment to the 800 MHz range. Once again this left some of the rural areas unable to communicate with these agencies. With the implementation of the cellular phone, most of the ambulance to hospital communication is accomplished with phone calls, where cellular service is available.
EMS communication in Texas has been improved greatly over the past two decades, but the communications industry is changing faster than most of the EMS agencies in Texas can possibly keep up with. Cellular communications has improved communication between agencies. As cellular coverage expands, interagency communications have and will continue to improve.
In 1987, House Bill 911 was passed, forming the Advisory Commission on State Emergency Communications (911 Commission). Their primary role is to facilitate the implementation of the use of 911 in Texas. This has eventually made public access to EMS available statewide and much easier.
EMS Communications Today
Approximately eighty percent of the twelve thousand EMS dispatchers in Texas are employed by law enforcement agencies. In many cases, EMS communications needs become secondary to law enforcement communications due to a lack of manpower, resources and a lack of understanding of EMS needs. Very few of these telecommunicators have the necessary formal education, knowledge of Emergency Medical Services or its communications needs. With the implementation of Emergency Medical Dispatch (EMD), the telecommunications professional is better equipped to deal with medical emergencies.