Here's the Know-How

Providing real-time information to building occupants

• By Peter Ebersold
• Sep 01, 2011

The term mass notification originated with the Unified Facilities Criteria (UFC) document 4-021-01, titled Design and O&M: Mass Notification Systems, created by the Department of Defense (DoD). The UFC outlines the design, operation and maintenance of mass notification systems (MNSs) required on all DoD properties, including posts for the Air Force, Army, Marine Corps and Navy.

The UFC defines mass notification as “the capability to provide real-time information to all building occupants or personnel in the immediate vicinity of a building during emergency situations. To reduce the risk of mass casualties, there must be a timely means to notify building occupants of threats and what should be done in response to those threats. Pre-recorded and live-voice emergency messages are required by this UFC to provide this capability.”

The UFC recommends the use of a combined fire alarm and mass notification system, particularly in new construction of military facilities, where the building fire alarm control panel forms a single combined system that performs both functions. For smaller buildings, the public address system may also integrate with this combined system, provided the PA system can be supervised for integrity.

Codes and Components
Initially seen as a solution for the military, MNSs are gaining popularity outside the armed forces. The 2010 edition of NFPA 72: National Fire Alarm & Signaling Code’s lengthy Chapter 24 outlines requirements for the design and installation of emergency communication systems within commercial facilities. While recent events such as the Virginia Tech campus shootings and severe weather incidents have raised demand for emergency communication systems for commercial properties, the new NFPA codes have begun to set a precedent of using fire alarm systems to support the added duties of a supervised and more survivable ECS.

So that MNSs serve as more than a common fire alarm voice evacuation system, NFPA 72 requires that “security personnel should be able to effect message initiation over the MNS from either a central control station or alternate (backup) control station. Where clusters of facilities exist, one or more regional control stations might also exercise control.” It also requires the MNS to offer a “dynamic library of scripted responses to various emergency events that would be easily customizable to meet the needs of the individual customer.”

To service this need, distributed messaging units, commonly referred to as local operator consoles (LOCs), are typically tied to the fire alarm/ECS network and installed throughout a facility or campus to provide authorized users a means systems such as e-mail or reverse-911 systems offer alternative methods for alerting occupants. However, these technologies are not supervised for faults or breaks, nor do they encompass a more “survivable” design that would enable the ongoing delivery of accurate communications even if one or more parts of the system’s network were down. Likewise, there are no codes or standards in existence that require these systems to be regularly tested and maintained to a specific level of performance.

NFPA 72 makes clear that distributed recipient notification systems such as text messaging or e-mail shall not be used in lieu of required audible and visual alerting emergency communication systems. This is due to the possibility of delivering conflicting information such as a text message directing a person to remain in place while the fire alarm system in the building provides the evacuation message. If the fire alarm evacuation system is activated before the occupants receive the message, there could be confusion.

For the same reason, NFPA 72 requires that a building’s fire alarm and emergency communication systems be integrated and programmed to allow all ECS functions to supersede the fire alarm. This priority setting avoids the situation of a fire alarm evacuating a building while a message to “shelter in place” is sent through the same facility’s ECS.

Today, a layered approach using a fire alarm/ECS and an integrated distributed recipient notification system is considered the best solution for reaching the largest number of occupants. However, the sequence of notifications -- from all systems -- must be considered, and any potential delays in the transmission of communications must be minimized.

For these reasons, all systems should be integrated and coordinated with a facility’s emergency plan.

In the middle of an emergency, flashing strobes accompanied by live or pre-recorded audible instructions tend to have a much higher effect on occupants.

At the same time, highly visual signs in large areas of assembly can offer information specific to the emergency or display a simple message such as “evacuate.” To deliver voice instructions to those outside, large speaker clusters can be installed on the exterior of a building or throughout a campus.

Using a combination of audible and visual notification devices, such as strobes, voice communications (indoor speakers and outdoor Giant Voice variety speakers) and programmable LED signage is considered the most intrusive solution for capturing the attention of occupants and delivering a clear, audible message.

For multiple buildings or campuses spread across a city, state or even the globe, some fire alarm manufacturers such as NOTIFIER have harnessed VoIP technology to deliver live voice messages to anywhere in the world via the Internet. These state-of-the-art systems include one or more workstations from which security or facilities personnel can send emergency communications via VoIP.

Fire alarm system manufacturers and installers work within a tightly regulated industry, which was the first to create requirements for the design and installation of ECS for commercial properties. The marriage of ECS and fire alarm control systems is a growing trend that is expected to continue reaching into larger varieties of facilities and multi-building properties, including K-12 schools, high-rise buildings, mass transit hubs and even public gathering places such as theaters, restaurants and places of worship.

This article originally appeared in the September 2011 issue of Security Today.