Survival in the great indoors
When it comes to fire and life safety, large venues require big thinking.
By Todd Alford, System Sensor U.S., St. Charles, Ill.
Commercial buildings keep getting bigger. Indoor malls are adding entertainment venues and restaurants. For example, in May 2012 Finance & Commerce.com reported the Mall of America is planning a $200 million expansion plan that includes hotel, office space, more retail space, and a medical clinic. Even office structures and universities are becoming more elaborate with larger atria and open spaces. The New York City Council approved a massive construction project for New York University that will allow the university to erect four buildings that together will add a skyscraper’s worth of classrooms, dorm rooms and office space, which was reported in the New York Times on July 25, 2012. But bigger is not always better in terms of protecting large indoor properties. Rather, better technology and smarter planning can offer greater protection.
Integrated multi-detection devices, such as those sensing heat, smoke, and carbon monoxide, are emerging to take a more inclusive approach to protecting indoor spaces. Voice evacuation systems for sharing important instructions are gaining traction and are borrowing intelligibility principles from similar public address system devices.
These technologies, as well as aspiration systems—very early warning systems that detect during the incipient stage of a fire—and other newer devices have great potential for detecting danger and improving egress in some applications within large indoor properties.
The sophistication of protection in large indoor venues varies widely. According a report by the NFPA Fire Analysis and Research Division, 15 of the 17 large-loss fires in 2010 occurred in these structures. Many of these did not have automatic suppression systems; some didn’t even have functioning detection equipment or “human error” overrode the protective systems. The fires in these 15 structures, which included several public assembly buildings and large facilities, resulted in a total property loss of about $369.8 million.
- A deliberately set fire at the 1.4 million-sq-ft Roseville Galleria shopping center in California caused $110 million in damage.
- Two of the fires were reported in churches, including the historic, 8,000-sq-ft Provo Tabernacle in Utah, which reported a $15 million loss.
- A 300,000-sq-ft Louisiana restaurant and a 37,000-sq-ft South Carolina golf course country club each had damages of $10 million.
Large-loss fires capture attention due to the sheer magnitude of the fire and life safety challenge: How do you choose the right technologies to detect fires and protect people and property within facilities that could be the length of a football field or more? What is the proper trade-off between system types, cost, and coverage? How far do our responsibilities in systems design extend?
As cited in Home Insurance Co. of Illinois v. National Tea Co., a deli oven in one shopping mall store started a fire that destroyed the store and caused water and smoke damage to other mall stores. The trial judge concluded that the store in which the fire originated was solely responsible for the damage. The mall owners complied with all applicable building codes and therefore were not negligent.
In “Premises Liability for Shopping Mall Fire Safety,” an essay by John O. Hayward, he states that although tenants are liable in these cases, mall owners, who essentially act as landlords, should protect tenants from harm resulting from foreseeable activities taking place within these areas.
As the uses and designs of large public facilities continue to evolve, fire and life safety system planners would be well advised to go beyond meeting code and protecting each party’s legal obligations. By incorporating longer-term thinking for diverse uses and occupancies, engineers can help drive more thorough and responsible fire and life safety system designs.
Consider the client
Admittedly, making the case for a more technologically advanced system can be challenging, depending on a number of factors, not the least of which is the client. When the client is a contractor in a design/build situation, cost is king, and the contractor may not appreciate any design that exceeds minimum code requirements. In that case, it may take some careful negotiation to convince the contractor to discuss with the building owners what levels of risk they may be exposed to with a minimum-code approach versus a more reliable or advanced fire and life safety system.
Kevin Kimmel, a senior fire protection engineer with architectural/engineering firm Clark Nexsen in Norfolk, Va., has designed safety systems for numerous occupancies and large, indoor structures. He says tuning into building intent during the planning phase is key. If the architect and the client have spent hours in planning meetings talking about their design concepts and the beautiful interior for a new casino, then a design engineer needs to respect how important visuals are for the project.
“That’s when you pull the architect off to the side and explain, ‘We can do beam detection or discreet air sampling, and it will increase costs just slightly. Otherwise, you’ll have this,’” he says, while showing a photo of the 20 highly visible white spot detectors that will clash with the interior finishes and overall design aesthetic. “You want to make sure when you’re in those meetings that you’re listening to their mission so your system doesn’t interfere with that environment.”
It’s ideal, then, to promote more technologically advanced systems while appealing to the goals and objectives of others involved in the decision-making process—even when it’s a less critical safety design priority such as aesthetics.
A fire and life safety system is just one component of a commercial property, however. “The owner is not just sweating detectors and fire alarm systems; he’s looking at carpeting, furniture, lights, U.S. Green Building Council LEED points, all these other things that go into design,” says Kimmel. “We have to understand our place as part of a huge system, and it has to all flow together.”
For example, a fire suppression system can limit the amount of damage a fire causes, but if it activates in error, the suppression system itself can cause costly damage or interfere with mission-critical activities. In this case, fire sprinkler monitoring devices are used to ensure fire sprinklers work properly.
Type of occupancy also matters in large facilities, whether it’s transient with a changing mix of people who are unfamiliar with the environment or nontransient with a fairly steady set of people who regularly frequent the space. Even within the institutional and commercial residential building segment, these occupancies can differ. It’s possible to prepare dormitory residents for building evacuations or run test drills for more nonfire emergencies, such as a shooting or severe weather conditions. In a hotel with new guests arriving every day, however, the focus shifts to informing occupants during the crisis.
This makes for a disturbing paradox: the occupants who best know their environments have more warning of and preparation for potential emergencies than those in transient environments who most need this information.
It’s understandable, however. Hoteliers, retailers, and theater owners do not care to worry their customers with troubling details that would detract from their enjoyment. Plus, it would be unimaginable from a business standpoint to require a convention center to evacuate show attendees for a disaster drill; the value of such an exercise would be questionable in any case.
Fire protection engineers should balance the sometimes conflicting needs of protecting occupants and building assets with protecting a facility’s main mission, be it entertainment, financial interests, education, or other possibilities.
Egress is the primary consideration for fire and safety in general. In larger buildings, the size of the building and the travel distance for people to evacuate must be considered. One approach would be to include directional sound technology within the fire or emergency communications system to guide occupants to the nearest safe exit.
Triggered by the fire alarm control panel, directional sound technology emits a broadband sound frequency that occupants intuitively follow to safety outside of the building, decreasing evacuation times by up to 75%. This helps to ensure that occupants who are unfamiliar with the building’s egress routes or emergency plans can quickly escape the building safely—even in smoke-filled or darkened buildings with little or no visibility.
Although a fire and life safety contractor usually commands a good understanding of the occupancy and structural type, it’s also wise to evaluate all possible uses—current and future—as well as the conditions under which the fire and life safety systems will operate.
While forming an idea of what constitutes normal, everyday use for a large building is fairly simple, it’s also easy to overlook unusual circumstances or application changes that can affect the environment. These out-of-the-ordinary instances could be seasonal in nature, related to special occasions such as concerts and other performances within a shopping mall that impact noise and foot traffic, or physical additions such as a waterfall in a hotel lobby that could muffle notification devices or create problems due to high humidity. When designing for intelligibility, it is important to consider worst-case scenarios for ambient noise, and to provide a voice evacuation system that would meet those requirements.
It’s very important to consider who will be the end user and the proper testing and maintenance of fire protection features and devices, according to Kenneth Bush, a fire protection engineer for the Maryland State Fire Marshal’s Office in Easton, Md. “Because each fire and life safety concept is designed on a case-by-case basis, each design has its own special combination of fire protection features that often rely on each other to obtain the desired levels of protection. Therefore, it’s imperative each system component is properly maintained, tested, and will always perform its intended function. Even the best design strategy relies heavily on the successful operation and coordination of each component device.”
Thinking about who will maintain the system once it’s installed is equally important. The most sophisticated system design and latest products are only exceptional if the people maintaining them are trained to maintain and monitor them properly. Training can be as simple as using the Internet and webinars or a computer-based meeting to go over important best practices, strategies, and processes.
Planning for the ordinary and the extraordinary within the framework of what’s normal in fire and life safety system design is just part of the picture. Engineers and contractors also have to balance cost efficiencies, environmental applicability and suitability, and the business interests of all involved parties, among many other factors.
Todd Alford is the marketing manager for the Commercial Business Unit of System Sensor U.S. where he leads a team that develops and markets next-generation fire and smoke detection technologies. Prior to joining System Sensor in 2007, he spent 11 years in the automotive industry in a variety of customer service engineering and marketing roles. Alford has bachelor's degrees in both architecture and engineering.