Fire Suppression Today

Fire Suppression Today

Construction firms are usually very diligent in installing fire suppression systems in offices and other facilities that house a lot of employees. It's important to make sure that warehouses and DCs are equally well protected. On June 30, 2007, a new Unde

The only time that warehouses tend to make the evening news is when one goes up in flames. The bad news is how often this happens. It's almost impossible to total up the number of warehouse fires that occur each week. On May 12, 2007, for example, a large fire gutted a warehouse in Chicago and was extinguished, but reignited two days later. On May 13, a fire in Buffalo, N.Y., burned through three warehouses. Heat was so intense that it melted some of the steel beams, and two of the three structures were called a total loss.

The good news is that, as often as warehouses tend to go up in flames, deaths and injuries tend to be less frequent than they are in hi-rise apartment fires, office building fires and industrial fires. Still, deaths do occur, and most of these involve those who arrive on the scene shortly afterward: the firefighters. A warehouse fire in Worcester, Mass., on December 3, 1999, killed six firefighters. The fire was such an inferno that it took six days to extinguish, and two more to locate the remains of the six firefighters.

According to the National Fire Protection Association (NFPA), the leading causes of fire in storage facilities are: arson (the most common cause); open flames, embers, or torches (from activities such as welding and cutting); electrical equipment (such as wiring, transformers, circuit breakers); other equipment (such as fuel-powered and electricpowered equipment, including forklifts); and chemical reactions between incompatible chemicals.

While non-warehouse fires tend to be more costly in terms of lives, warehouse fires tend to be more costly in terms of property loss. According to a report written by Keith Roemer of insurer FM Global (Johnston, R.I., www.fmglobal.com), the average loss for all fires and explosions is $941,000, while the average loss for storage facility fires is $1,400,000. The Worcester fire mentioned above, for example, led to $16.1 million in damages. Other extreme losses include a 2005 fire at a winery warehouse in Napa Valley California that ended up costing about $100 million in lost wine. And a September 26, 2006 fire in Sacramento that caused millions of dollars in damage to a piano warehouse.

New Fire Equipment Standard
On June 30, 2007, a new fire protection standard from UL (Underwriters Laboratories, Northbrook,
Ill., www.ul.com) goes into effect. UL 864, which covers fire alarm equipment manufacturing standards, is the first major revision to UL's standard in nine years, and it attempts to follow changes in the life safety codes, most notably NFPA 72 from the National Fire Protection Association (www.nfpa.org). These changes have forced fire alarm manufacturers to redesign or update a significant portion of their entire product lines.

Among others, the new UL standard covers NFPA 13 (sprinklers), NFPA 15 (water spray systems), NFPA 16 (foam water systems), NFPA 17 (dry chemical extinguishing), NFPA 17A (wet chemical extinguishing), NFPA 92A (smoke control), and NFPA 2001 (clean agent extinguishing systems). The standard calls for better synchronization of notification appliances, greater software integrity, broader programming requirements, and updates in supervision, monitoring, compatibility, and power transmission.

"In short, fire alarm products listed in accordance with the Ninth Edition of UL 864 carry with them the confidence and assurance of meeting, or exceeding, the latest industry safety standards," says Mike Lynch, senior v.p., engineering, for Honeywell Fire Systems (Northford, Conn., www. honeywelllifesafety.com) in a February 14, 2007, press release. "For the public, it will be a springboard to better, safer fire alarm products; and for building owners, architects, and engineers specifying UL 864 Ninth Edition listed products, they can be confident that their fire alarm system is equipped for the demands of the 21st century."

Notifier by Honeywell (Northford, Conn.) is one manufacturer being affected by UL 864. Notifier (www.notifier.com) manufactures commercial fire alarm systems and technology, including control panels, network systems, integrated systems, and peripherals.

"We manufacture our products in compliance with UL 864, which is designed to align with NFPA 72," says Peter Ebersold, director of marketing. As noted earlier, UL 864 hasn't been revised for nine years. As a result of the recent revision, Notifier has redesigned and re-engineered its entire product line. "Since technology has evolved so much in recent years, this has allowed us to put a much more robust product in the field, which also meets all of the new requirements of NFPA 72," he says.

For example, with the older technology, the systems were set to respond to alarms within 90 seconds. With the new technology, they are designed to respond in ten seconds. Another advantage: Since there are so many more radio frequencies in operation today (from cellphones, Wi-Fi networks, etc.) than there were when UL 864 was last revised, the new systems are much more immune to interference, which could cause false alarms and false discharges.

Certainly, if a facility has an old system (five years or older), this is definitely a good time to consider replacing it with the new UL 864-compliant technology. But should warehouses with relatively new systems discard them and replace them with the new systems?

"If the local fire authority mandates it, then certainly yes," says Ebersold. However, if it is not mandated, then as long as the system is under five years old, you may want to keep what you have until it is time to replace it.

Modern Sprinkler Systems
According to Chris Jelenewicz, engineering program manager for the Society of Fire Protection Engineers (Bethesda, Md., www.sfpe.org), the fire protection equipment industry is always working hard to provide more flexibility for warehouse and DC managers.

"When you install a fire suppression system, you want to know that there is a lot of flexibility, based on the storage configurations," he says. One of the most important innovations in flexible system design is the advent of ESFR (early suppression fast response) sprinklers, which have revolutionized warehouse fire protection, because of the flexibility they allow.

"They detect the fire a lot quicker than standard sprinklers and, at the same time, they provide more water with larger droplets," says Jelenewicz. "As such, theyare much more effective in extinguishing high-challenge fires, which is very importantin warehouses with rack storage that is over 20 feet high."

The traditional sprinkler, the kind that are typically installed in office buildings, schools, and other commercial locations, were also installed in warehouses and DCs prior to the advent of ESFR technology.

"If storage was over 12 feet high, warehouses had to install standard sprinkler systems in the ceilings, as well as in the racks at certain intervals," he says. In-rack systems work well where a lot of material is stored in large industrial shelving one on top of the other. If the system is only installed in the ceiling, and something in the middle rack caught fire, the water would not extinguish the fire until it reached the top rack. Problems with in-rack systems, of course, were cost and lack of flexibility. Another problem was the potential for damage to the sprinkler heads or pipes as stored items were placed into and pulled out of the racks.

Another alternative is the "large drop" sprinkler, which is similar to an ESFR head. "As with ESFR systems, large drop sprinklers only need to be installed at ceiling level, rather than also within the racks," Jelenewicz says. "The large drop system provides faster detection as well as providing more water."

Still, according to Norman Saenz Jr., associate principal with KEOGH Consulting (Lewisville, Texas, www.keogh1.com), to be safe, there are benefits to considering ESFR systems and in-rack systems. KEOGH provides warehouse design services, including safety and fire protection. "We don't design, engineer, or install these systems; we simply consult on what should be used," he says.

Saenz points out that there is no single guidance document on warehouse fire protection that everyone follows. Requirements are based on local fire codes. However, in general, his company recommends that, if the building is 50- or 60-feet high, managers should probably consider a ceiling system and an in-rack system.

"If you have a 25- to 40-foot building, then ESFR by itself should be sufficient," he says. Certain inventories, such as hazardous materials and flammable products, may require in-rack sprinkler systems. In addition, if there is wood plank racking, in-rack sprinklers are usually also required. "ESFR can't penetrate this," he says.

If you do have an in-rack system, it is important to realize that, "once it's in place, it is in place," says Saenz. "It is very expensive to tear it out and move it, so you want to think really hard at first about how you want to lay things out, how you are going to expand, etc."

One company that doesn't want to take any chances with fire suppression is L.L. Bean, Inc. (Freeport, Maine, www.llbean.com). According to David Lockman, C.S.I.T., manager of engineering, distribution and returns operations, the company utilizes ESFR sprinkler heads in areas that require them. Next, the warehouses and offices are completely covered by an integrated fire suppression sprinkler system.

"In addition, some of our racking incorporates in-rack sprinklers for added protection," he says. Finally, the warehouses are partitioned off in multiple sections via Factory Mutual rated firewalls, and the door systems are integrated to close automatically in the event of an alarm.

Constant Vigilance
While installing the right system is critical to fire suppression success, monitoring the system is equally important. "You need to periodically evaluate your system, especially if you are changing configurations or are storing new products or materials," says Rich Kovarsky, a forensic engineer, and president of Pyro-Technical Investigations, Inc. (Cincinnati, Ohio, www.ptiforensic.com), an investigation firm that studies, among other things, sprinkler and extinguisher system failures.

In the investigations that Kovarsky conducts, he finds a number of reasons for the failure or inability of extinguisher systems to put out fires. One is that the building was reconfigured after the original installation.

"What would have been an effective system as built is not effective as is," he says. He investigated one warehouse that had a sprinkler system, but an office and two restrooms had been built and partitioned off later. However, the sprinkler system hadn't been extended to these rooms. "The office caught fire, and by the time the sprinkler system was activated, the fire was too large for it to be effective," he says.

Another cause is a change in products being stored in the warehouse, products or materials other than what the original sprinkler system was designed for. One example is that many auto parts warehouses are storing more products made of magnesium, such as wheels and intake manifolds.

"Magnesium burns, and water not only doesn't work well on a magnesium fire, it actually causes the fire to get worse," says Kovarsky. "Better options are foams or dry chemicals."

Another recommendation, even in warehouses that use dry-pipe systems it is still important to do maintenance. "You can get condensation in dry-pipe systems, and the pipes can crack, causing flooding," says Kovarsky.

Fire Suppression Recommendations
The standard for inspecting and maintaining any type of water suppression system is NFPA 25. "This is being widely used, and it is important to understand this standard and the testing requirements in it," says Chris Jelenewicz, engineering program manager for the Society of Fire Protection Engineers (SFPE, Bethesda, Md., www.sfpe.org).

Make sure you have a reliable and adequate water supply. "You need to test these systems, including the valves and pressure, on a regular basis," he says.

Anytime you change the storage configuration or introduce new products or materials into the warehouse, you need to make sure that the fire suppression system remains adequate. "It is always good to have a fire protection engineer evaluate the changes to make sure you are adequately protected," says Jelenewicz. Remember that sprinkler systems are generally engineered to cover specific commodity classifications in specific storage configurations. Any changes to these classifications and configurations (e.g., new products, new racking designs) can render a sprinkler system inadequate to control fires.

It's a common misconception that sprinkler systems are designed to extinguish fires. They are usually only designed to suppress fires until the fire department arrives. A good system, though, one that is installed properly and well-maintained, will be able to suppress a fire and minimize losses until additional help arrives.

The ONYX series of intelligent fire alarm systems from Notifier by Honeywell.

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