Risk Analysis Demystified

Published On
Nov 1, 2017

I know from experience with contractors in the field that, when it comes to mass notification systems (MNS), being required to perform a risk analysis for the MNS ranks just above getting a root canal at the dentist’s office!

When most of us think of “cool tools,” we think of a product we can use to make an installation easier or quicker. However, some tools are not made of metal and rubber. NFPA 72 2016, National Fire Alarm and Signaling Code, has a helpful checklist tool to assist designers with performing risk analyses. 

First, understand that there is no option to allow an MNS installation in a building without performing a risk analysis, because the code requires every MNS to be designed with the anticipated risks for each facility. 

Also, in Section, the code states, “the designer shall consider both fire and non-fire emergencies when determining risk tolerances for survivability for the mass notification system.”

You need to know if the MNS is expected to perform during a fire; if not, survivable cable or wiring methods need to be used. The code allows the risk analysis to address the communication scenarios spelled out in an existing emergency response plan. However, it is still required to perform a risk analysis based on the facility’s complexity.

Most contractors don’t normally determine the occupancy characteristics when designing a fire alarm system or an MNS, but an MNS requires that the risk analysis “consider the number of persons, type of occupancy, and perceived peril to occupants.” Most installation contractors do not think a whole lot about the maximum occupant load of a building, but Chapter 24 of the code requires the risk analysis to be based on the maximum occupancy load calculation for “every occupiable room, building, area, space, campus, or region is expected to contain.”

Additionally, there may be elements in a building that are not inherent in the system design but do affect occupant behavior or rate of hazard development. When this occurs, those issues must be included in the risk analysis. 

In a general sense, the code suggests the risk analysis should consider six categories: natural hazards, geological events; natural hazards, meteorological events; natural hazards, biological events; human-caused, accidental events; human-caused, intentional events; and technological-caused events.

The code requires an MNS to ensure occupants are notified of an emergency as determined by the risk analysis. The code reminds the designer that the extent to which occupants and personnel must be notified will be based on the anticipated events outlined in the risk analysis based on the above general list.

The cool tool I mentioned before is in the Annex A information for Section Here are the general categories of questions from Annex A that might be presented to the senior manager responsible for MNS decisions. The actual questions for each project should be tailored to the area, the building, the campus, and the culture of the user organization. The following is a brief description of potential content within the mass notification event questions:

“(1) What is the type of emergency event—that is, is it fire, security, safety, health, environmental, geological, meteorological, utility service disruption, or another type of event?

“(2) What is the urgency of the emergency event—that is, does it represent immediate danger, has it already occurred, is it expected to occur soon, is it expected to occur in the future, or is its occurrence unknown?

“(3) What is the anticipated or expected severity of the emergency event—that is, how will it impact our facility and its functions, is it expected to be extreme, severe, etc.?

“(4) What is the certainty of the emergency event—that is, is it happening now, is it very likely to occur, is it likely to occur, is it possible that it will occur in the future, is it unlikely to occur, or is its occurrence unknown?

“(5) What is the location of the event, or from what direction is the emergency event approaching—that is, has it or will it be approaching from the north, south, east, or west?

“(6) What zone or areas should receive the emergency message(s)—that is, is it a floor of a building, multiple floors of a building, the entire building, multiple buildings, a campus of buildings, an entire town or city, an entire state, an entire region of states, or an entire country?

“(7) What is the validity of the emergency event—that is, has the emergency event been investigated and/or confirmed?

“(8) What instructions should we send to our personnel—that is, should they evacuate the facility, should they shelter-in-place, should they shelter-in-place at a special location, should they proceed to a safe haven area, and other action oriented items?

“(9) Are there any special instructions, procedures, or special tasks that we need to remind personnel about or to accomplish—that is, close your office door, open your office door, stay away from windows, do not use elevators, and other information relating to personnel actions?”

Not all of these may be appropriate for every MNS installation. In any case, it is important to remember that, when an emergency event occurs, the response must be immediate and deliberate. There is no time for indecision.

About the Author

Wayne D. Moore

Fire/Life Safety Columnist

Wayne D. Moore, a licensed fire protection engineer, frequent speaker, writer and expert in the life safety field, has been a principal member and chair of NFPA 72, Chapter 24, as well as a former principal member of NFPA 909 and NFPA 914. He is the...

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