Mobile/Portable Radio Information

The Emergency Communications Center (ECC) transmits on 800 MHz. CARS apparatus each carry 800 MHz walkies as follows:

When the ECC receives a 911 call for a medical emergency, the call taker transfers the call to the medical dispatcher. When the call is transferred, information such as the caller's telephone number and address are displayed on a computer screen, where the medical dispatcher then enters additional information about the call. The medical dispatcher then decides which medical protocol number and priority is required, and then which rescue squad agency is to respond to the call. While the call is dispatched, other required agencies such as fire and/or law enforcement are notified to respond as well. If the call is life threatening, the medical dispatcher may give life saving instructions to the caller.

The appropriate rescue squad is notified of the call over the radio system. First, a station tone will sound indicating their station is due. Second, a series of beeps indicates the level of the call.

ECC then announces the address, nature of call & agency to respond. Simultaneously, a dispatch is made through selected groups on the SnapPager network to alert special interest groups (TRT, WRT, press, Duty Officer, etc.) of particular calls. A hard copy of the ECC computer input screen is faxed to the appropriate agency for the crew assigned to the call. The responding units then sign-on advising they have received the call and that they are en-route. ECC then relays any additional information on the call through both the radio and that unit's SnapPager and then monitors status changes in the units responding.

When an ambulance transports a patient to the hospital, they are required to call that hospital and give a radio report on the nature and condition of the patient. The EMT's may elect to call for medical advice from a physician, but they only do this under unusual circumstances. When the ambulance arrives at the hospital the crew then completes their PPCR call sheet with data from RIDS, and then it is then placed in the patient's hospital chart. Times & changes in patient's condition are important for physician's to make decisions in treating their patient.

Hospital Radio Channels

CARS ambulances are equipped with Motorola Max-Trac mobile radios. These radios are located in the patient compartment and are used to communicate with the hospitals to relay patient information. These radios can also be used to communicate with ECC should the truck radio fail. The radio channels on the Max-Trac radios are as follows:

Simple Radio Terminology

A. Frequency: the actual number of cycles per second of a particular wave form. Frequency is usually expressed in megahertz MHz) form. Examples of frequency are as follows:

B. Channel: The local designation of a particular frequency or pair of frequencies for convenience of users. (Think of the pre-set buttons on your car radio.)

C. Simplex: A system where the radio transmits and receives on the same frequency. (Think of your CB radio walkie-talkies.)

D. Duplex: A system where radios transmit and receive on different frequencies.

E. Repeater: A device, which receives on one frequency and simultaneously re-transmits the traffic on another frequency.

Basic Guidelines For Radio Use

The manner in which telephone and radio communications are received and handled is definitely a measure of the efficiency and professionalism of an organization and a strong indicator of the attitude of its individuals. Observing basic rules will expedite message handling and improve working relationships among all agencies and individuals involved in any given incident, as well as enhance the public image of the agency. There are a lot of citizens out there that have scanner radios and they love to listen to emergency radio frequencies, EVERYONE HEARS WHAT YOU SAY ON THE RADIO! The following is a list of guidelines that should always be followed when communicating by radio.

* Make sure you radio is always on and the volume is properly adjusted.

* Reduce background noise by keeping windows in the vehicle closed. Press the PTT button and hold for a count of 2 before speaking. This prevents cutting out the first couple of words of your transmission.

* You should always listen before transmitting to make sure the channel is clear. The over-eager, excited, and/or unprepared operator is a source of confusion and frustration. Quite often, airwaves are tied up by needless babble.

* Do not use phrases like "be advised". They are implied and serve no useful purpose.

* Courtesy is assumed, so there is no need to say "please", "thank you", and "your welcome".

* "Affirmative" and "negative" are preferred over "yes" and "no" because the latter are difficult to hear.

* During all radio operations, REMAIN CALM! Avoid uncivil, angry, abusive, derogatory or sarcastic remarks and language. If you are angry at field personnel or otherwise irritated, the radio is NOT the place to get even or vent your displeasure!

* Avoid transmitting when sirens are operating: yelling over sirens and other ambulance noise is usually unreadable and is unnerving for the listener.

* Make sure the microphone switch is fully depressed for one full second before starting to talk, especially when transmitting on a repeated frequency. Hold the microphone close to, but not touching, the mouth and talk directly to it - not across it. Talk at a conversational level - don't shout.

* Speak distinctly and pronounce words carefully. Speak at a moderate speed, using conversational tone of voice with natural emphasis and rhythm. Messages that are rapid-fire, slurred, or otherwise garbled can lead to confusion and prolonged air time. Messages should be spoken in phrases, not one word at a time.

* Use official titles and authorized unit and equipment designations in all transmissions; e.g., "EMT Smith with Medic 140."

* The use of plain English is preferred over the use of "10" codes and "signal" codes to avoid potential confusion: these codes are not standard from agency or jurisdiction to another. Standard radio phrases are encouraged to be used.

* Keep all transmissions brief and to the point. Avoid lengthy descriptions and unnecessary repetition; however, include all pertinent information. Accuracy, brevity and speed are all important. When asked for a brief medical report by a receiving facility (e.g., UVA MEDCOM), simply give the age, sex, and chief complaint of your patient and your ETA. It is likely that a request for a brief report is due to heavy radio/telephone traffic, so KEEP IT BRIEF!

* Do not call simply to establish contact with a known manned dispatch station. When possible, simply identify yourself and send the message.


[Unit] ECC, this is Medic 141
[Dispatch] Medic 141, go ahead
[Unit] Medic 141 is on-scene
[Dispatch] Okay Medic 141, 12:04


[Unit] ECC, Medic 141 is on-scene
[Dispatch] Okay Medic 141, 12:04

* When calling a station, identify the station to be called and then yourself. By doing so, you will obtain the attention of the station being called, and they will know what party is calling them. When calling a multiple frequency hospital it is helpful to identify the frequency you are calling on. Reversal of caller/receiver, use of only unit numbers/names, and omission of operative words ("to", "this is...") can lead to confusion and should not be practiced.

* When calling your base hospital for consultation and/or orders ("medical command"), MAKE SURE you have done a complete assessment, provided all immediate care measures, and have your thoughts organized to "paint the picture" for the Medical Command Physician (MCP). This way you sound competent, confident and concise (the 3 C's), and don't waste air time or vital treatment time having to get missing information requested by the MCP. Use the telephone whenever possible.

* If you request medical command, be ready to give report when you are informed the physician is standing by. It is VERY annoying to busy ER physicians to be called for consult to be told to "stand by" -- YOU should be ready for the consultation. Only in the case of "crashing" patient should you ask medical command to wait on you.

* During lengthy transmissions, stop occasionally and ask the MCP if he/she has understood what has been said so far. A good rule of thumb is to transmit for up to 30 seconds, then ask for confirmation.

* Avoid codes, slang, or abbreviations that are not authorized.

* The best people on the radio are the ones you never hear. They keep transmission short and to the point and use the telephone whenever possible.

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