Designing an effective emergency communication system

Catastrophic events have changed the way fire protection engineers design emergency communication systems and mass notification systems.

By Robert J. Libby, PE, FSFPE, Hagatna, Guam; and Jon M. Evenson, LEED AP, Chica May 22, 2012

May I have your attention please, may I have your attention please, there has been:

  • a fire emergency reported in the building
  • a bomb threat alert issued for this building
  • dangerous weather conditions reported in this area
  • an intruder sighted in or around the building
  • a hazardous chemical release reported.



  • leave the building by the nearest exit or exit stairway—do not use the elevators
  • evacuate immediately using the nearest exit; further instructions will be issued outside the building
  • stand by for further instructions
  • report any suspicious activity
  • defend in place.

These are examples of messages broadcast to occupants in a building with a voice emergency communication system (ECS) that incorporates mass notification capabilities. They are examples of prerecorded messages, but new ECSs have the ability to override the prerecorded messages and provide a live voice broadcast via a handheld microphone located at the fire alarm control panel. Not too long ago, only the first message—“a fire emergency has been reported”—would have been broadcast from a fire alarm system.

Mass notification systems (MNS) have been around for as long as mankind. From messengers in the Roman Empire, to smoke signals for Native Americans, to town criers in Colonial days, there has always been a need to broadcast messages to a great number of people simultaneously. As technology improved, so has the ability and need to reach broader audiences with accurate and current information to reduce the risk of mass causalities from an event.

Several catastrophic events have changed the landscape for ECSs. After the 1996 attack on Khobar Towers in Saudi Arabia that claimed the lives of 19 servicemen and injured hundreds, the Secretary of Defense issued a report that identified there was no effective system to warn the occupants. Although a service member had become aware of the impending danger, and his efforts to run from floor to floor warning the occupants saved many lives, he was unable to reach everyone in a timely manner. This prompted the military to develop a force protection standard under the Unified Facilities Criteria, UFC 4-010-01 Minimum Antiterrorism Standards for Buildings, defining the need for mass notification. In its definition, specific direction was given to “providing a timely means to notify building occupants of threats and what should be done in response to those threats to reduce the risk of mass casualties.” Certainly other significant catastrophes also impacted the need for the further development of communicating during emergencies, including the World Trade Center collapse in 2001 and the Virginia Tech massacre in 2007.

The Khobar Towers bombing prompted the development of UFC 04-021-01 – Design and O & M: Mass Notification Systems. The U.S. Air Force petitioned the National Fire Protection Assn. (NFPA) to develop a national standard for MNS. This task was accepted by NFPA 72 and then referred to as The National Fire Alarm Code. NFPA expanded the scope of the Signaling Systems for the Protection of Life and Property to include mass notification. Through the efforts of this task group, the 2007 Edition of NFPA 72 was able to include provisions to use the fire alarm notification system for other uses, such as warning of dangers other than fire. This was a big step, as fire alarm systems were always considered somewhat “sacred” and not to be mixed with any other functions.


The 2007 edition of NFPA 72 included some milestone revisions related to ECS. Most importantly, the definition of emergency voice/alarm communication systems was changed to no longer reference fire emergencies, but more generically a system to provide voice instructions. This version also included the first definition of MNS: “A system used to provide information and instructions to people, in a building, area site, or other space.”

NFPA 72 2007 edition Chapter 6 – Protected Premises Fire Alarm Systems, contained three important factors for using a combined system. A combined system was any system that contained non-fire-related components. This was the foundation for the MNS requirements. Speakers could now be used for MNS, and setting mass notifications as a priority during emergencies was acceptable if the items in Table 1 were followed.

Table 1 – NFPA 72, Chapter 6 References

NFPA 72 (2007 Edition) section


“Speakers used as alarm notification appliances on fire alarm systems shall also be permitted to be used for MNS.”

“In combination systems, fire alarm signals shall be distinctive, clearly recognizable, and, with the exception of mass notification inputs, take precedence over any other signal even when a non–fire alarm signal is initiated first and shall be indicated as follows in descending order of priority unless otherwise permitted by this code:”

“Live voice instructions originating from the protected premises fire or MNS shall override all previously initiated signals….”

Annex E, although not enforceable as a requirement, provided extensive information and discussion on the use and design of MNS. Although not written in a standard’s enforcing format, Annex E introduced many significant ideas and technologies related to MNS. Chapters introduced included: Fundamentals of Mass Notification Systems, System Fundamentals, Documentation, and System Features.

Developing an ECSFollowing the publication of the 2007 Edition of NFPA 72, the National Fire Alarm Code underwent an extreme makeover in the scope and organization of the document, at which time a new Technical Committee was formed for ECS (SIG-ECS). The committee of 28 professionals and 12 alternates created an entirely new chapter to address requirements for communicating information using a variety of systems during any multitude of events. Along with the changes, the NFPA 72 document was renamed for the 2010 Edition as the National Fire Alarm and Signaling Code, which exemplifies the scope change from fire emergencies to all forms of warning systems and communication systems that are used during emergencies. The committee, as with all committees within NFPA technical code development, was purposely made up of professionals from a variety of backgrounds and experience including special expert, installer/maintainer, enforcing authority, manufacturer, user, labor, and research/testing.

During the writing and development of the new chapter, the committee decided to organize the material into sections on Application, Purpose, General, One-Way ECS, Two-Way In-Building ECS, Information Command and Control, and Performance-Based Design, which includes the Risk Analysis (see Figure 1).

NFPA 72, Chapter 24 required that prior to the design and installation of an ECS, a risk analysis and emergency response plan be developed to assist in the design and operation of the system. The risk analysis is supposed to help the end user identify potential risks and vulnerabilities that the system may need to address in the time of an emergency. The risk analysis needs to be completed on a site-by-site basis with specific information gathered about the site, site operations, and the construction of the building(s) identified as part of the ECS.

One of the most critical aspects of an ECS is how the system will function and who will coordinate the activation, communication, and management of response efforts related to the emergency event. For a successful system design, the risk analysis must be established before any equipment is specified.

The risk analysis requires careful planning and implementation. An effective risk analysis is conducted by either an internal or external assessment team that understands the operations of the site. This team should include various functions related to site operations, engineering, maintenance, and management. The goal of the risk analysis is to identify current and potential risks/threats to a site and also identify elements that need to be addressed in the emergency response plan and the design of the ECS.

Risks that could potentially affect the site include:

  • Building systems
  • Humans
  • Terrorism
  • Weather.

All of these emergencies could have an impact on the site and how the ECS is designed and operated.

Designing and specifying an ECS or MNS requires significant planning and analysis. For a basic ECS, determining factors should include such variables as:

  • Location of control equipment and the emergency control center
  • Defining inputs, such as smoke, heat, manual stations
  • Defining the zones for notification appliances
  • Determining accessible features, such as the need for and location of visual appliances (strobes)
  • Speaker placement for audibility and intelligibility
  • Survivability of circuits if staged evacuation is desired.

When adding MNS features, many more variables need to be considered, which should be addressed in the risk analysis. These include features such as:

  • Will the MNS be combined with the fire alarm? And if combined, will they be different or from the same manufacturer?
  • What speakers will be used for the MNS? A fire alarm, or additional speakers such as a PA system?
  • Will notification be provided outside the building?
  • Who will have access to live paging? If multiple microphones are provided, who will have priority over messages?
  • Will other visible notification appliances be needed, such as different colored or labeled strobes, textural messages (LED signs), video monitors, pagers, e-mails, or text messages?
  • Will messages be prerecorded and if so, how many messages, and what will they convey?
  • How will the messages be prioritized?
  • What other inputs, besides fire detectors, will be used, such as chemical monitors, weather alerts, or emergency broadcast alerts?
  • How will occupants be directed? Will they be told to evacuate, relocate, defend in place, or a combination of the above?

The risk analysis is also a key component to the proper development of an emergency response plan for a specific site. The emergency response plan should include the following elements:

  • Team structure and responsibilities
  • Standard operating procedures (SOPs)
  • Documentation
  • Training and exercises.

Information on the proper elements to be included in the emergency response plan is identified in NFPA 1600, Standard on Disaster/Emergency Management and Business Continuity Programs.

 Bringing it together

The team structure should be developed based on the site’s operational capabilities and identified specific roles and responsibilities to address key aspects of the site operations. Team members should include personnel from operations, security and life safety, finance and legal, public relations, infrastructure, and systems. Each group should have clearly identified responsibilities and coordination steps outlined for the various emergencies that could affect the site and/or operations. Clear lines of communications between the team members are essential.

The SOPs should be developed as a site-specific response strategy to assist the site manager during the initial minutes/hours of an emergency until the arrival of the local authorities and hand-over of command from the site to these authorities. SOPs should be developed in accordance with the threats and potential emergencies identified in the risk analysis and should provide team members with specific tasks to complete in the various phases of an emergency. Specific attention should be paid to how these SOPs coordinate with the local authorities’ capabilities and response strategies to limit potential confusion during the initial phase, prior to the arrival of the authorities.

The emergency response plan should include operational strategies for the use of an ECS before, during, and after an emergency affects a site. In addition, the operators of the ECSs need to have clear operational instructions on how and when the ECS is to be used during an emergency.

Documentation and follow-up are critical to the success of an emergency response plan. The documentation is required to track the response efforts that are taken before, during, and after an emergency. Also it provides the site with the ability to review response steps taken and modify the overall strategy based on issues noted during or after the response. Documentation is also valuable to the local authorities who arrive on-site and need an understanding of what has been done and how the site operates. Documentation could include team structure information, site operations information, occupant information, special assistance required information, site system information, and other documents and drawings that could aid the response efforts.

The emergency response plan needs to be developed as a living document that is continually updated and managed to ensure the accuracy of the information in the plan. Out-of-date or wrong information could create vulnerabilities in the site emergency response plan’s effectiveness both during and after an emergency.

Continual training is key

The effectiveness of the emergency response plan is based on two factors: (1) risk analysis information and (2) training and education of team members. The risk analysis will assist in the design of the emergency response plan and ECS, but the training and education of team members is vital to the smooth implementation of the emergency response plan. The training and education of team members, and even building occupants, will assist in a coordinated approach to identify, coordinate, respond, and recover from an emergency affecting the site.

Training and education should include a tier approach to train and test team members. Training should include classroom training, ECS operational training, table-top exercises (TTX), and full-scale exercises (FSE). Each of these training tiers has positives and negatives, but a good combination of these tiers will result in a comprehensive emergency response training and education program that will prepare team members to respond appropriately in an emergency.

Classroom training is ideal to provide emergency response plan information in a basic format with little interaction or role-playing. This type of training is ideal for introducing the plan and discussing the core elements of the plan with large groups.

ECS operational training is essential for those team members who are responsible for the activation and management of the ECS before, during, and after an on-site emergency. The proper use of the system before, during, and after an emergency can limit the negative impacts on the site operations, occupant notifications, and initial response. The plan and operation of the systems needs to be practiced by the team members responsible for the systems. In addition, this type of training can also identify if the ECS is in proper working order and capable of providing clear, intelligible notifications to team members and occupants.

TTXs are designed to provide the core team members with a site-specific emergency situation and allow them to walk through the response steps in a controlled environment. TTXs are an ideal way to test a team’s capabilities and responsibilities without interrupting the site’s normal operations.

FSEs are live drills to test the team members’ capabilities in a real-life setting. FSEs provide valuable insight into issues and concerns that could adversely affect the response due to site conditions or operational challenges. FSEs are more difficult to coordinate due to the interruption to normal site operations, but can provide the most benefit if properly designed and implemented.

Finally, involving the local authorities during the risk analysis and emergency response plan development and training is an important aspect. The local authorities are those professionals that are involved with emergency response on a daily basis and will provide professional response assistance when notified. Their involvement in the planning and training portions of the emergency response plan can create a good working relationship and teach them about the site and the daily operations. Coordinate response strategies are aimed to minimize response times and maximize the effectiveness of the emergency response plan and ECS.

As ECS technology continues to advance, specific care must be taken to address the operational and educational aspects of emergency response to ensure the response strategies and responsibilities also continue to evolve. Failure to address the operational and educational sides of ECSs may open up liabilities and create unsafe/unsecure conditions for building occupants and staff.

Forward strides

What can we expect for the future? First it must be noted that with the exception of the military, MNS are not required. Whereas NFPA 72 provides excellent guidance on the design and installation, including development of the risk analysis for MNS, the document is a design tool and not enforceable unless it is required by a building or fire code. Current building and fire codes require ECSs in certain occupancies, such as high-rise buildings, large assembly occupancies, and malls, but the requirements generally are limited to one-way ECSs, such as those provided by a fire alarm system.

Universities currently are required to provide timely notification to students, faculty, staff, and visitors in the event of an emergency under the guidelines outlined in the Jeanne Clery Act. The Clery Act is one of the driving forces for universities to examine their current emergency response and communication capabilities. The act requires universities to report, on an annual basis, their crime statistics. As of July 2010, amendments to the Clery Act require universities to identify their emergency response planning and communications capabilities. In addition, the amendments require universities to report their method of testing of their emergency communication capabilities and training of staff in emergency response planning.

If a school fails to comply with the requirements outlined in the Clery Act, it may be subject to fines and other negative ramifications, including loss of federal financial aid. Universities should use the NFPA 72 requirements outlined in Chapter 24 to review and enhance their current emergency response and communication capabilities.

Libby serves as the executive vice president of the western Pacific region for RJA. He is actively involved in the design and installation of numerous MNS and serves on the NFPA 72 – National Fire Alarm and Signaling Code, and on the ECS committee. Evenson serves as the director of emergency management for RJA. He is actively involved in the development and implementation of emergency response programs and ECSs. He is currently a technical member of NFPA 72, 99, 730/731, and 1620.