Chapter 4 – EMS System Communications1

Chapter 4 – EMS System Communications

  1. Objectives

Knowledge Objectives /
  1. Define communications.
  2. Describe the role of the Federal Communications Commission in EMS system communications.
  3. Describe the following components of an EMS communications system: base station, mobile two-way radio, portable radio, repeater, digital radio equipment, cellular telephone.
  4. Discuss the role of an Emergency Medical Dispatcher in a typical EMS event.
  5. List the proper methods of initiating and terminating a radio call.
  6. List the correct radio procedures during each phase of a typical EMS call.
  7. Discuss the communication skills that should be used when interacting with individuals from other agencies.
  8. Identify the essential components of the verbal report.
  9. Explain the importance of effective communication of patient information in the verbal report.
  10. State legal aspects to consider in verbal communication.

Attitude Objectives /
  1. Explain the rationale for providing efficient and effective radio communication and patient reports.

Skill Objectives /
  1. Perform a simulated, organized, concise radio transmission.
  2. Make a brief, organized report to give to an Emergency Medical Technician or paramedic arriving at an incident scene where you were the first on the scene.

  1. Preparation

Corresponding textbook pages: /
  • 104-115

Audiovisual equipment: /
  • Chapter 4 PowerPoint® presentation
  • Computer
  • Multimedia projector

Course administration materials: /
  • Attendance sign-in sheet

  1. Personnel

Primary instructor qualifications: /
  • One Emergency Medical Responder instructor knowledgeable in EMS communications

Assistant instructor qualifications: /
  • The instructor-to-student ratio should be 1:6 for psychomotor skill practice.
  • Individuals used as assistant instructors should be knowledgeable about EMS communications.

IV.Key Terms Presented in This Lesson

  • Automatic Vehicle Locator (AVL) A device that uses the Global Positioning System (GPS) to track a vehicle’s location.
  • Base Station A transmitter/receiver at a stationary site such as a hospital, mountaintop, or public safety agency.
  • Communication The process of sending and receiving information.
  • Computer-Aided Dispatch (CAD) A computer system that aids dispatch personnel in handling and prioritizing emergency calls.
  • Duplex System A mode of radio transmission that uses two frequencies to transmit and receive messages, allowing simultaneous two-way communication.
  • Emergency Medical Dispatcher Certified personnel who receive 9-1-1 calls, verify the address and emergency, assign responders, provide prearrival instructions to the caller, communicate with the responders, and record incident times.
  • Emergency Medical Radio Service(EMRS) A group of frequencies designated by the FCC exclusively for use by EMS providers.
  • Federal Communications Commission (FCC)The United States government agency responsible for regulation of interstate and international communications by radio, television, wire, satellite, and cable.
  • Global Positioning System (GPS)Technology that uses a system of satellites and receiving devices to compute the receiver’s geographic position on the earth.
  • Interagency Radio Advisory Committee (IRAC) The federal agency responsible for coordinating radio use by agencies of the federal government.
  • Mobile Data Computer (MDC) A computer mounted in an emergency vehicle that displays information pertaining to the calls for which EMS personnel are dispatched.
  • Mobile Two-Way Radio A vehicular-mounted communication device that usually transmits at a lower power than base stations.
  • Multiplex System A mode of radio transmission that permits simultaneous transmission of voice and other data using one frequency.
  • Portable Radio A handheld communication device used for radio communication away from the emergency vehicle.
  • Public Safety Answering Point (PSAP) A facility equipped and staffed to receive and control 9-1-1 access calls.
  • Repeater A device that receives a transmission from a low-power portable or mobile radio on one frequency and then retransmits it at a higher power on another frequency so that it can be received at a distant location.
  • Simplex System A mode of radio transmission that uses a single frequency to transmit and receive messages.
  • Transmitter A device that sends out data on a given radio frequency.
  • UHF Ultra-high frequency radio band (a band is a group of radio frequencies close together).
  • VHF A very high frequency radio band (a band is a group of radio frequencies close together).
  • Voice over Internet Protocol (VoIP) Technology that allows users to make telephone calls by means of a broadband Internet connection instead of using a regular telephone line; also known as Internet Voice.

V.Skills Presented in This Lesson

  • There are no skills identified for this lesson.

VI.Lesson Outline

Slide # / Instructor Notes
1 / A.Communications
2 / 1.Objectives
3 / B.Communications Systems
4
Objective 1 / 1.Communication is the process of sending and receiving information.
2.Effective communication requires that we send and receive this information using an understandable and commonly recognized language.
a.Using terminology that is too technical or too advanced may create confusion.
b.Information that is misunderstood can lead to inappropriate treatment or care.
c.To alleviate this potential problem, most EMS systems in the United States require the use of clear text or speech to relay data from one point to another.
5
Objective 2 / C.Regulation
1.The Federal Communications Commission (FCC) is the United States government agency responsible for regulation of interstate and international communications by radio, television, wire, satellite, and cable.
2.The FCC is charged with the development and enforcement of rules and regulations pertaining to radio transmissions.
3.In addition, the FCC is mandated to do the following:
a.Control licenses and allocate frequencies
b.Establish technical standards for radio equipment
c.Monitor frequencies for appropriate usage
d.Spot-check for licenses and records.
 Remind your students of the importance of speaking in a professional manner during radio communication. Inappropriate language or use of radio frequencies may lead to enforcement action by the FCC.
6 / D.Radio Frequencies and Ranges
7 / 1.Very high frequency (VHF)
a.VHF radio frequencies can be subdivided into low band and high band.
1)A band is a group of radio frequencies close together.
b.VHF low band
1)Radio waves in the low-band frequency range bend and follow the curvature of the earth.
a)Allows radio transmission over long distances
b)Subject to interference by atmospheric conditions, including weather disturbances and electrical equipment
2)Because these radio waves do not penetrate solid structures (such as buildings) well, VHF low band is less effective for use in metropolitan areas.
c.VHF high band
1)Radio waves travel in a straight line.
a)Easily blocked by topography such as a hill, mountain, or large building
b)Although less interference occurs in this band than in VHF low band, its susceptibility to interference by solid structures may result in gaps or “holes” in radio coverage.
2)Generally better for use in metropolitan areas than VHF low band
8 / 2.Ultra-high frequency (UHF)
a.Radio waves travel in a straight line
1)Can reflect off or bounce around buildings
2)Shorter range than VHF high or low bands
3)Greater ability to enter buildings or structures through openings or mediums that are radio-frequency permeable
b.Often requires the use of repeaters because of its short range
1)A repeater is a device that receives a transmission from a low-power portable or mobile radio on one frequency and then retransmits it at a higher power on another frequency so it can be received at a distant location.
 “Line of sight” and “straight line” radio coverage problems are generally overcome with the use of repeaters placed on high ground or on top of a large structure or tower.
9 / 3.800-Megahertz frequencies
a.800-MHz frequencies are UHF radio signals that use computer technology to make transmissions more secure than the other types of radio transmission.
b.Allow clear communication with minimal interference
c.Use a trunking system, which allows routing of a transmission to the first available frequency
d.Although 800-MHz frequencies generally have a limited range and are very straight line, these problems are overcome by using multiple repeaters. This makes 800-MHz frequencies very effective for use in urban areas.
10 / E.Communications Equipment
11
Objective 3 / 1.Base station
a.A base station is a transmitter/receiver at a stationary site such as a hospital, mountaintop, or public safety agency.
b.At a minimum, a base station is made up of a transmitter, a receiver, a transmission line, and an antenna.
c.A transmitter is a device that sends out data on a given radio frequency.
d.A radio signal generated by the base station may be sent directly to a receiving unit or to a repeater as needed.
12 / 2.Mobile two-way radios
a.A mobile two-way radio is a vehicle-mounted communication device.
1)Usually transmits at a lower power than base stations (typically 20 to 50 watts)
2)Typical transmission range is 10 to 15 miles over average terrain
b.Transmission over flat land or water increases range.
c.Urban areas, mountains, and dense foliage decrease transmission range.
13 / 3.Portable radios
a.Handheld device
b.Typically have power output of 1 to 5 watts, limiting their range
c.Used for radio communication away from the emergency vehicle
d.May have a single channel or multiple channels
e.Often used in conjunction with repeaters to increase transmission range
14 / 4.Repeater
a.A repeater is designed to receive a lower-powered transmission and then boost the signal for retransmittal. This may allow for greater geographical coverage and can assist with the transmission of portable signals to other units in the system.
b.Repeaters can be fixed or mobile.
c.For portable communications, repeaters may be located in the vehicle or on radio towers. Mobile communications use repeaters on radio towers.
d.Repeater signals can be retransmitted by radio waves, microwaves, or telephone landlines.
15 / 5.Digital radio equipment
a.Digital pagers
1)Used in many EMS systems
2)An audible signal and/or text message can be transmitted quickly by the dispatch center to alert EMS personnel to respond to a call.
b.Mobile data computer (MDC)
1)Computer mounted in an emergency vehicle
a)Also called mobile data terminal or MDT
2)Computer displays information pertaining to the calls for which EMS personnel are dispatched.
a)Text from dispatch pertaining to the call
b)Address of the incident
c)Local map indicating location of the incident
3)Used to log response times and indicate the status of the EMS crew/vehicle
a)In service and available for calls
b)On the scene
c)Responding to a call
d)En route to the hospital
4)Also used to send and receive text messages between the EMS crew and the dispatch center
c.Automatic vehicle locator (AVL)
1)Many EMS vehicles are equipped with an AVL device.
2)Uses the global positioning system (GPS) to track a vehicle’s location
a)GPS uses a system of satellites and receiving devices to compute the receiver’s geographic position on the earth
16 / 6.Cellular telephones
a.Geographical areas are divided into “cells.”
b.Each cell has a base station to transmit and receive signals.
c.Cellular communication systems can track a mobile unit’s movements from cell to cell and transfer the unit’s radio activity to the appropriate cell base station.
17 / F.Transmission Modes
1.Four transmission modes are generally used in an EMS communications system: one-way, simplex, duplex, and multiplex.
2.One-way transmission mode
a.Generally used for paging systems
b.In one-way mode, a signal is sent to any unit monitoring the appropriate frequency, but the receiving unit has no ability to transmit a message.
3.Simplex system
a.Uses a single frequency to transmit and receive messages
1)Only one signal may be transmitted or received at a time.
2)Simultaneous radio transmissions will block a message from being received.
b.Advantage: allows the speaker to relay her message without interruption
c.Disadvantage: takes away the ability for discussion regarding a patient or situation
4.Duplex system
a.Uses two frequencies to transmit and receive messages, allowing simultaneous two-way communication
b.Advantages: either party can interrupt as necessary; aids discussion regarding a patient or situation
c.Disadvantage: user at each end has a tendency to interrupt the other
5.Multiplex system
a.Permits simultaneous transmission of voice and other data using one frequency
b.Advantages: either party can interrupt as necessary; two-way communication aids discussion regarding a patient or situation
c.Disadvantage: voice signals can interfere with data transmission
18 / 6.9-1-1
a.Official national emergency number in the United States and Canada
b.Enhanced 9-1-1
1)Routes call to 9-1-1 center closest to caller
2)Automatically displays caller’s phone number and address
3)Most 9-1-1 systems are Enhanced 9-1-1 systems.
 If a 9-1-1 caller does not speak English, the 9-1-1 call taker can add an interpreter from an outside service to the line. Communications centers that answer 9-1-1 calls also have special telephones for responding to 9-1-1 calls from deaf or hearing- and speech-impaired callers.
19
Objective 4 / G.Dispatch
1.Emergency medical dispatchers (EMD)
a.Knowledgeable about
1)Geography of the area
2)EMS system’s capabilities
3)Activities of other public-service agencies
b.An EMD is responsible for:
1)Verifying the address of the incident
2)Asking questions of the caller
3)Assigning responders to the incident
4)Alerting/activating responders to the incident
5)Providing prearrival instructions to the caller
a)CPR, choking, bleeding control
6)Communicating with responders
7)Recording incident times
 Telephone conversations with the caller and telephone and radio transmissions between the dispatch center and police, fire, and EMS personnel are recorded. Courts have forced dispatch centers to release tapes of 9-1-1 calls in response to lawsuits by the media, attorneys, or other involved parties. These 9-1-1 tapes may subsequently be heard on radio and television news. With this in mind, always be professional when communicating with others in the workplace and on an emergency call.
20 / 2.Computer-aided dispatch (CAD)
a.CAD is used in many EMS systems.
b.When a call comes in to a PSAP that uses CAD, the address and phone number of the caller are automatically entered into the CAD system.
c.Dispatcher types a description of the emergency into the computer and then assigns a priority level to the call.
d.An “event” is created for which many activities related to it can be tracked, retrieved, and evaluated.
e.Software used by the CAD system can connect dispatchers with local, state, and national computer database systems.
21 / H.Guidelines for Effective Radio Communication
22
Objective 5 / 1.Make sure that you have checked that your equipment is available and in good working order at the start of your shift.
2.Before speaking into the radio:
a.Make sure the radio is on and the volume is properly adjusted.
b.Reduce background noise as much as possible.
c.Listen to the frequency that you will be transmitting on to make sure that it is clear before speaking.
d.Hold the radio’s microphone 2 to 3 inches away from your mouth.
e.Locate and press the “push to talk” (PTT) button. To make sure your first words are not cut off, pause (with the PTT button depressed) for 1 to 2 seconds before speaking.
23 / 3.Using a normal tone of voice, address the unit being called by its name and number. Then identify the name of your unit (and number, if appropriate) as determined by your local protocols.
4.Wait for the unit being called to signal you to begin your transmission by saying, “Go ahead,” or some other term standard in your area. A response of “Stand by” means, “Wait until further notice.”
5.When the unit being called has acknowledged your call (and has stopped speaking), relay your message.
a.Speak clearly, keeping your transmissions brief.
6.At the end of your message, the unit being called may repeat back the pertinent information from your message to make sure that the unit has received the information correctly. If the information is verified as correct, acknowledge the unit’s transmission and announce that you are clear.
24 / 7.Use plain English in your radio communications. Avoid the use of “ten codes” and slang.
8.Avoid meaningless phrases, such as “Be advised.”
9.Do not use profanity on the air (the FCC may impose substantial fines).
10.Avoid words that are hard to hear like “yes” and “no”; use “affirmative” and “negative.”
11.Courtesy is assumed; there is no need to say “please,” “thank you,” and “you’re welcome.”
12.When transmitting a number that might be confused with another, give the number, then give the individual digits. For example, do not say “fifty one.” Instead, say “five one.”
13.Do not offer a diagnosis of the patient’s complaint or injury. Remain objective and impartial in describing patients.
 Many EMS personnel incorrectly assume that the calltaker in the dispatch center has every piece of information needed to assist with the proper care of your patient. The reality is that in some cases the caller is too excited, frightened, confused, or reluctant to deliver the needed information.
25 / I.En Route to the Call
26
Objective 6 / 1.The format for your radio report may be determined by local or state protocols.
2.The following “script” may help you understand a typical call.
a.The script below begins with the electronic or tone activation of a radio or pager.
b.We will use “Medic 51” to indicate your communication with dispatch.
3.DispatchCenter:
a.“Medic 51 (five, one), respond code 3 to 4321(four, three, two, one) East Main Street for a report of difficulty breathing. Call number 987 (nine, eight, seven). Time out 1402 (one, four, zero, two).”
4.Medic 51:
a.Dispatch, Medic 51 (five, one) received. Responding to report of difficulty breathing at four, three, two, one East Main Street.”
5.DispatchCenter:
a.“Medic 51, Dispatch received, you are responding. Caller reports your patient is 70-year-old female in the kitchen of this address. The door will be unlocked. 1403.”
6.Medic 51:
a.“Dispatch, Medic 51, received. 70-year-old female in the kitchen and the door will be unlocked.”
27 / K.Arrival at the Scene
28
Objective 6 / 1.Additional radio contact with the dispatch center will be needed on your arrival at the scene.
2.Medic 51:
a.“Dispatch, Medic 51. We are on scene.”
3.DispatchCenter:
a.“Medic 51, Dispatch received, on scene at 1406.”
 Remind your students to never enter a scene unless given specific clearance or they have determined that it is safe. Advise them to always consider a plan for an emergency exit if there is any threat to their safety.