Emergency Voice Communication System (EVCS)
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Data Management
What is an Emergency Voice Communication (EVC) system?
An Emergency Voice Communication (EVC) system (also referred to as EVCS) is a fixed, monitored, two-way voice communication system that enables point-to-point communication during an emergency.
In simple terms, it provides direct two-way speech between:
- a central control point (e.g., building control room, fire control point, or a panel location), and
- multiple remote points called outstations (installed at strategic locations around a building).
Many EVC systems are full duplex, meaning both parties can talk and listen at the same time (like a normal telephone call). This improves clarity during high-stress incidents compared with “push-to-talk / one-at-a-time” systems.
Where is EVC used?
EVC is commonly installed in:
- Refuge areas (for occupants who cannot use stairs or protected escape routes unaided)
- Firefighting lobbies/stairs/fire control points (to support firefighter communications)
- Stadia and large assembly venues (to support steward/marshal communications)
- Large or complex sites where radio communications may be unreliable in parts of the building
EVC Building Regulations guidance
In England, Approved Document B (Fire safety) – Volume 2 includes guidance for refuge areas and EVCs. For example:
Refuges should be provided with an emergency voice communication (EVC) system complying with BS 5839-9.(Approved Document B, Volume 2, paragraph 3.7)
The same paragraph also explains that the refuge EVC arrangement should use Type B outstations communicating with a master station located in the building control room (if one exists) or next to the fire detection and alarm panel.
Common purposes include:
- Compliance with recognised standards and fire-safety guidance.
EVC systems are typically designed and maintained in line with BS 5839-9 (code of practice for emergency voice communication systems). - Incident command and firefighter communications
Enables firefighters and incident controllers to coordinate actions when operating in different locations. - Refuge communication (reassurance + coordination)
Provides a way for a person waiting in a refuge to:
– confirm their location,
– request assistance,
– receive reassurance and instructions. - Steward/marshal communication (where applicable)
In venues such as stadia, steward telephones can support managed evacuation procedures.
Not a public address system: An EVC system is generally point-to-point communication. If you need building-wide messages to all occupants, that is normally delivered by a Voice Alarm/PA-VA system (often designed to BS 5839-8), not by EVC.
Intended uses for an EVCS
In the early stages of evacuation, before the fire and rescue service arrives, the EVC system may be used between the control room and fire wardens/marshals on various floors or stewards at a sports venue.
Typically, a floor can call the control centre to say it has been cleared.
The fire and rescue service would usually take control of the evacuation upon arrival, with a fire officer at the control centre communicating with other officers via the EVC system.
During a fire, the fire and rescue service would continue to use the EVCS. A mobility-impaired person or anyone who can’t use an escape route can identify their presence and communicate with the control centre.
Disabled Refuge
A Disabled Refuge area is a safe place for people who can’t use fire escapes and evacuation lifts to call for help and wait during a building evacuation. When stairwell crowding eases, building management and emergency services can safely help these people leave.
Mobility impairment is defined as being unable to walk 200m without assistance, for example people with arthritis, leg and back injuries, and pregnant women over 6 months.
Typical EVC system architecture
Most EVC systems are built from the following parts:
- Master station/control equipment (central control point)
This is the “hub” where calls are received and managed. It may include:
– call indication (which outstation is calling),
– ability to select and speak to individual outstations,
– system status and fault indication,
– log/event functions depending on the product. - Outstations (remote communication points)
Outstations are installed at defined locations and allow a call to be initiated to the control point (or allow the control point to call them). - Power supplies
EVC is a life-safety communication system and is normally provided with:
– a mains supply, and
– a standby supply (e.g., batteries), so that it remains available during power interruptions. - Cabling/network topology
Depending on the system design and product, the wiring may be:
– radial (star), loop, or networked arrangements,
– supervised for faults (open circuit, short circuit, device removal, etc.).
EVC outstation types ( UK terminology)
EVC systems commonly include the following outstation types:
TYPE A outstations – Fire telephone system
– Typically handset-based (telephone-style)
– Used by firefighters and trained personnel
– Provides direct voice communication with the control point
TYPE A outstations – Emergency/steward telephone system
– Similar concept to fire telephones but used by designated emergency staff, stewards, or marshals
– Common in stadia and managed evacuation venues
TYPE B outstations – Disabled Refuge System (DRS)
– Typically hands-free (or accessibility-oriented)
– Located at refuge points
– Allows a person waiting in a refuge to communicate with the control point for assistance and reassurance
Example manufacturer
A well-known UK manufacturer of EVC systems is Baldwin Boxall, whose published guidance explains EVC concepts, typical outstation types (Type A, Type B, combined units), and intended use.
[1] Marlowe Fire & Security, “Emergency Voice Communication Systems .” (accessed Jul. 20, 2022).
[2] GOV.UK – Approved Document B (Fire safety), Volume 2 (Buildings other than dwellings) (accessed Jan. 05, 2025).
[3] Baldwin Boxall – “What is EVC?”. (accessed Jan. 05, 2025).
[4] British Standard – BS 5839-9 (EVC Systems)
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