Radio communication is the operational backbone of a live event. When the PA system needs to alert stewards before a public announcement, when security needs to communicate with medical about a patient location, when the production manager needs to tell the stage manager to hold the show — radio is the channel that makes coordinated response possible. When radio systems fail, whether from dead zones, battery depletion, channel congestion, or inadequate coverage, the event’s ability to respond to incidents degrades proportionally.

Radio communication planning is not simply a matter of buying enough handhelds. It involves frequency coordination, channel architecture, coverage testing, battery management, protocol development, and personnel training — all of which must be completed before the event opens.

Radio System Architecture: Channels and Talkgroups

A live event requires a structured radio channel plan that assigns separate channels (or talkgroups on digital systems) to distinct functional groups. A single shared channel for all event personnel quickly becomes unusable at any event of meaningful size — the channel saturates with routine traffic, time-sensitive messages are delayed or lost, and personnel in different functional areas cannot communicate without disrupting each other’s operations (Federal Emergency Management Agency [FEMA], 2010; DHS, 2017).

A standard channel architecture for a medium-to-large live event includes:

• Command channel: used exclusively by the Incident Commander and department heads for command-level coordination. This channel is not used for routine operational traffic.
• Operations channel(s): used by event staff for routine operational communication. At larger events, multiple operations channels may be assigned by functional area (production operations, venue operations, ticketing and entry).
• Security channel: dedicated to security operations, enabling security to communicate about incidents, personnel deployments, and threat intelligence without cluttering the general operations channel.
• Medical channel: dedicated to the medical team’s internal communications. Keeping medical traffic on a separate channel is a requirement for events with substantial medical operations — see the medical communications discussion in Chapter 5 materials.
• Emergency channel: a designated backup channel to which all personnel can be directed in the event of primary channel failure or congestion during a major incident. All personnel must know this channel designation in advance.
• Interoperability channel: where local emergency services use different radio systems, a designated interoperability channel or gateway allows event command to communicate with responding fire, EMS, or law enforcement agencies (DHS, 2017).

Each channel must have a designated primary user and a designated backup user who monitors the channel and responds when the primary is unavailable. Channels that are nominally assigned but not actively monitored by a responsible person are not functional channels (FEMA, 2010).

FCC Licensing and Frequency Coordination

In the United States, radio communications on most frequencies require licensing by the Federal Communications Commission (FCC). Large events typically use licensed business band frequencies in the VHF or UHF bands, which provide good coverage in both indoor and outdoor environments and support the range of radio equipment typically used in event production. License-free MURS (Multi-Use Radio Service) and FRS (Family Radio Service) frequencies are available for small events but are shared public frequencies that may experience interference at high-traffic events (FCC, 2023).

Frequency coordination — the process of identifying available frequencies in the event area and coordinating their use among all event radio users to avoid interference — must be completed before equipment is purchased or rented. Large outdoor events, particularly those using multiple production systems with radio-controlled equipment (wireless microphones, lighting control, pyrotechnic triggers), require professional frequency coordination to avoid interference between production systems and event communications systems (FEMA, 2010; FCC, 2023).

Coverage Testing

Radio systems must be tested under event conditions — meaning with the physical structures, audience masses, and production equipment in place — before the event opens. Radio coverage that is adequate in an empty venue may be inadequate once production infrastructure is erected, temporary structures are in place, and the audience is present. Dense crowds, metal structures, concrete, and large equipment all attenuate radio signals.

A full perimeter walk test — conducting radio communication checks from all points on the perimeter and all key locations within the venue — identifies dead zones before the event opens. Dead zones can often be addressed by repositioning repeaters or antennas, but this requires time that is not available after the event opens. At outdoor sites, antenna and repeater positioning may require specific mast heights or locations to clear terrain obstacles or tree lines (FEMA, 2010).

Dead zone mapping — documenting where coverage is weak or absent — should be incorporated into the event’s communications plan. Areas with known dead zones require compensating measures: wired telephone connections, designated radio relay positions (a person stationed at the dead zone boundary to relay communications), or scheduled check-in protocols for personnel working in those areas.

Battery Management

Battery failure is one of the most common causes of radio communication failure during events. Batteries that were not fully charged before the event, that have been in service through a long prior shift, or that are at end of service life can fail during an incident — precisely when communication is most critical. Battery management requires (FEMA, 2010):

• All batteries fully charged at the start of every event or event day — not assumed to be sufficiently charged from a previous day’s use
• Adequate spare batteries at the command center and at department supervisor locations, enabling rapid battery swap without requiring personnel to leave their position
• Battery charging facilities adequate to charge all spares simultaneously during the event, enabling a continuous rotation of charged batteries
• A battery tracking system for large radio fleets — knowing which batteries were deployed when enables planned rotation before depletion rather than emergency response to a dead radio

In high-noise environments — near stage, near speaker arrays, near heavy equipment — standard radio speakers may be inadequate for receiving communications. Key personnel in these areas should be equipped with full ear-defending headsets that attenuate ambient noise while amplifying radio audio. This is both a hearing protection issue and a communications effectiveness issue (FEMA, 2010).

Radio Protocols and Training

A radio is only as effective as the person using it. Personnel who have never been trained in radio communication protocols contribute to channel congestion, unclear messages, delayed responses, and — in worst cases — failure to respond correctly to emergency communications. All employees equipped with radios must be formally trained in radio use before the event, covering (FEMA, 2010):

• How to use the assigned device: key functions, channel selection, volume control, emergency alert button if present
• Call sign discipline: using designated call signs consistently rather than names, titles, or informal references. Call signs must be unique and pre-assigned, not improvised during the event.
• Message format: the standard structure for radio communication — call sign, wait for acknowledgement, deliver message concisely, confirm receipt. Messages that begin without confirming the channel is clear, that are overly long, or that are unclear require repeated exchanges that consume channel time and can cause critical delays.
• The open mic procedure: an open microphone (a stuck transmit button) locks all other users off the channel or talk group. Every radio user must know the designated open mic response — typically, switching to a backup channel until the open mic is identified and corrected.
• Emergency escalation: the specific words or codes that signal an emergency requiring immediate response, and the correct response when receiving an emergency transmission.

Radio training should be conducted before the event, in a context that allows practice and questions. A five-minute verbal briefing at the gate before the event opens is insufficient. The National Incident Management System’s training resources (available at training.fema.gov) include free online courses covering ICS communications principles (DHS, 2017).

Telephone Systems as a Complement

Landline telephones — or wired field telephone networks in temporary outdoor settings — provide communication redundancy that cellular phones cannot guarantee. During a major incident, cellular networks in the area of the event frequently become overloaded as thousands of audience members simultaneously attempt to make calls, rendering cellular communication unreliable. Hard-wired telephone lines are not subject to network congestion and remain functional when cellular networks are saturated (FEMA, 2010).

External telephone lines in the command center designated for emergency use must never be used for routine event communication — they must remain available for outbound emergency calls to local emergency services. Command center telephone numbers must be provided to all external emergency service agencies before the event so that incoming emergency communications from those agencies can reach the command center directly without routing through an event switchboard (FEMA, 2010).

Production Intercom Systems

Production intercom systems — the wired or wireless intercom networks used by stage management, lighting, audio, and video departments — serve a distinct but complementary function to the event’s operational radio system. Production intercom provides the tight, real-time coordination between production departments that enables a show to run smoothly. It is not a substitute for the event’s operational radio system, and its failure does not excuse failure of the operational communications infrastructure.

Production intercom systems should be powered from a dedicated emergency power circuit, independent of the main event power distribution. In the event of a primary power failure, stage management’s ability to coordinate a safe halt of show operations — stopping flying effects, warning personnel of conditions, coordinating stage evacuation — depends on intercom remaining functional during the moments when power restoration is being managed (FEMA, 2010).

References

Department of Homeland Security. (2017). National Incident Management System (3rd ed.). FEMA.

Federal Communications Commission. (2023). Radio services: Business radio, MURS, and FRS. FCC. https://www.fcc.gov

Federal Emergency Management Agency. (2010). Special events contingency planning job aids manual. U.S. Department of Homeland Security.