Author(s): Thomas Scherpa. Published on September 1, 2017.

Human Factor

The alarm is going off, but nobody’s doing anything: Why even the best life safety systems need to be part of a response plan that accounts for human behavior.


A few years ago, I was in a major airport in the United States when a fire alarm went off. I had gone through security and was walking through a connector between terminals when the alarm sounded—a series of beeps, followed a voice recording that announced, “THERE IS A FIRE EMERGENCY IN THE BUILDING. PLEASE PROCEED TO THE NEAREST EXIT.”

My first reaction was to stop, listen to the recorded announcement, and look for an exit, though I admit I was looking for one that didn’t involve going back through TSA security, just in case it was a false alarm. I didn’t see an exit immediately, so I walked toward the nearest terminal and started looking for an exit door.

Not surprisingly, I appeared to be the only one doing this. I found an emergency exit door in the terminal, but before walking toward it (and trying to decide whether to risk some interesting interactions with airport security if I went through it) I noticed that the strobes and speakers were not going off in the terminal itself. My training as a fire safety professional began to kick in, and a few things quickly became obvious. The terminal was not separated from the connector by a fire-rated separation. The terminal was zoned separately on the notification system. There was no alert message in adjacent zones. And people working in the area, including airline employees, contractors, and security, didn’t seem to respond to the alarm at all.

At this point my curiosity got the best of me. I waited in the terminal (with an exit door at the gate behind me), near the connector where I could see and hear the alarm, and I watched. A few people looked up at the strobes, but aside from that nobody seemed to behave any differently than normal. This was true for both the general public and airport employees. Crowds of people kept right on walking into the connector area where the alarms were going off, only stopping to read the arrival and departure screens. Even the skycaps pushing passengers in wheelchairs kept on going. This continued for about 10 or 15 minutes, until the alarms stopped with no further announcement.

This reaction, or lack thereof, was concerning, not so much as it applied to the general public, which I expected, but how it described the behavior of airport personnel. Ever the optimist, I thought maybe airport employees had behaved the way they had because they possessed more information about what had triggered the alarm than the general public. I still had some time before my flight—a one-hour delay that eventually stretched to two—so I decided to ask some questions.

The first stop was the information booth in the middle of the connector area where the alarms had been going off. The attendant was quick to dismiss the event as a false alarm. When I asked how he knew it was false, he had a ready answer. “This happens from time to time, and nobody does anything different,” he told me. I asked how he would know if a real fire were occurring, and he responded, “I suppose I’d get a call…”

The next stop was my gate. I decided to check with the gate agent to see if she had heard anything about the source of the alarm. She hadn’t, but she mentioned that they did experience fire alarms a few times a week, including one that had occurred at about six o’clock that morning. I specifically asked about the skycaps, to see if they had any information about the nature of the alarm before pushing mobility-impaired people through the “fire” area. She told me that the alarms happened so frequently that the skycaps ignore them unless they get a radio call to tell them it’s a real emergency.

Two more questions immediately occurred to me: If employees don’t respond to an alarm without manual notification through other means, what purpose does the notification system serve? And who would be making the phone and radio calls to all the employees?

I kept those questions to myself.


I imagine that most readers have had at least one similar experience with a fire alarm in a public setting. In the few years since this event, I have had the same situation occur in two other major U.S. airports. In both cases, the public and employee responses were the same, and comments from airport personnel were similar. On another occasion, I was in a restaurant with members of an NFPA technical committee when the fire alarm went off. Our table was the only one to leave, and while we waited outside we watched people continue to walk into the building even as the fire engines rolled up outside.

Fortunately, all of these experiences were relatively benign. The concern is that they demonstrate weaknesses in the emergency response plan, issues that can have devastating effects. Employees are tasked with maintaining operations, but if they fail to respond to an emergency or respond inappropriately, the response plan will break down. A tragic example of such a breakdown was the Ycua Bolanos supermarket fire in Paraguay in 2004, which was described in detail in the November/December 2004 edition of NFPA Journal. In this incident, a fire originating above the supermarket’s food court quickly spread through the facility. Deficiencies in the market’s construction features and egress capacity limited the ability of shoppers to escape, resulting in nearly 400 fatalities and 360 injuries. While there were several aspects of that facility that did not meet NFPA codes, the actions of security personnel to lock doors to prevent shoplifting likely increased the number of casualties by further impeding egress.

We rely on fire alarm and emergency communication systems as critical life-safety systems in public assembly spaces, but how effective are they? Without a well-implemented response plan that factors in human behavior, even the best technological solution will fail. What would you do if you heard an alarm? Does the answer depend on where you are? Many workplaces conduct regular drills to ensure that employees know how to respond to a fire alarm. At home, you should have an escape plan prepared and be ready to respond when the smoke alarm goes off. But what about in a public space? Will your response be different? Should it be?

The need for validation is a recognized behavioral trait. When given an indicator of an abnormal condition, such as an alarm signal, most people will seek reassurance to validate the initial perception before taking any action. In an airport or retail facility, people would likely seek validation from an employee or security person on the presumption that they have additional information available to them. Social inhibition decreases the likelihood that an individual will respond to the initial indication; in a crowd of people, few are willing to be the first person to take action.

For guidance on considering these factors in emergency planning, facility managers and safety professionals can refer to Section 4.8 of NFPA 101®, Life Safety Code®, which describes the elements of an emergency action plan, including procedures for reporting emergencies and occupant and staff response to emergencies. The underlying behavioral and social effects are described in detail in the Handbook of Fire Protection Engineering, published by the Society of Fire Protection Engineers.

The public’s response in these incidents was expected, considering employees provided no validation. Unfortunately, the employee response was also understandable given the frequency of false alarms and the need to avoid disruptions to airport operations. When people are exposed to frequent false alarms, they become conditioned to ignore them.

The underlying lesson here for life-safety systems designers and facility managers is to recognize the normal behavioral responses and try to accommodate them with the design of safety systems. Key elements to consider include:

False alarms reinforce poor behavior. Most people have more experience with false alarms than true emergencies, so the assumption is that any alarm is false unless proven otherwise. This supports inaction over action, unless there is some other management system to promote action. Whenever possible, fire alarm testing and maintenance in public facilities should be planned to avoid generating alarms for the general public. When alarm activations are necessary during nonemergency situations, they should be accompanied by clear notification before the alarm and an “all clear” afterwards.

The latest and greatest technology by itself isn’t enough. Properly applied detection solutions can be used to reduce the frequency of false alarms, and specialized notification approaches including positive alarm sequences can further reduce inadvertent public notification. However, these systems will only be effective when they are implemented within a response plan that accounts for human behavior.

Employees are critical for influencing public behavior. The general public will tend to seek validation for ambiguous cues, and even not-so-ambiguous cues. If employees don’t respond properly, the general public probably won’t, either. Employees, including contractors and tenants, need to have clearly defined roles and the facility management needs to hold them accountable for performing those roles.

Fires are not the only emergencies. Public assembly areas need to consider a variety of threats, including active shooters, bomb threats, and severe weather, just to name a few. The desired response, both from employees and the public, may be different for each emergency. Heightened awareness of mass shooting events prompted mass evacuation of several terminals at the Los Angeles International Airport in August 2016 and New York’s Penn Station in April 2017 due to loud noises that were perceived as gunshots. Some facilities, including airports, have security and operational concerns—including screening for weapons, controlling admission, preventing shoplifting, and others—that can create major logistical challenges during an evacuation. Employees and responders should be trained to respond appropriately in each situation.

Even the best safety system will fail if people have been conditioned to respond inappropriately or not at all. By considering human behavior in the design of life safety systems, we can help ensure that fire alarm and emergency communication systems don’t become boxes on the wall that offer nothing but a false sense of security.

THOMAS SCHERPA is a fire safety consultant with DuPont in Sullivan, New Hampshire. Top Photograph: iStockPhoto