Not Just for Cowboys

In today's competitive market, most newly constructed stadiums include all the latest bells and whistles to accommodate demanding audiences and provide comforts for corporate partners and other VIPs. The stadiums, in turn, have rigorous fire safety systems and programs designed to protect and respond in the case of an emergency. With the modern advancements included in these venues, the system is challenged to provide an elevated level of protection.

The new professional football stadium in Arlington, Texas, is the largest, most technologically advanced entertainment venue to date. It includes unparalleled challenges for providing protection due to its unique and massive structural features. Designed by HKS and built by Manhattan Construction, the $1.2 billion stadium features:

- Two steel mega-arches, each 1,225 feet long to form the world's longest single-span roof structure,
- The world's largest high-tech HDTV-equipped LED scoreboard that extends from 20-yard line to 20-yard line, and
- An expansive retractable roof creating a 104,960 square foot opening.

The world's largest end zone doors

According to Mark Cryer, DFW Fire Protection Inc. project manager, the company that designed, engineered, built and installed the fire sprinkler systems in the stadium, two of the biggest challenges were coordinating the trades (electrical, HVAC, plumbing and fire protection contractors) and designing the fire sprinkler systems for the dome-shaped facility because it required flexible couplings.

"There was much to consider, including the hazards, NFPA 13 code, city codes, what the owner wanted, FM Global's standards (which are above everyone's), along with the products used to create the systems," said Cryer.

"It's designed to meet codes. In the end, my goal is to control a fire."

A massive stadium requires extensive, yet easy to install and maintain, fire and life safety systems that will work without fail. To accommodate the latest innovations included in the stadium and the large crowds during an event required more than 70 fire sprinkler systems that included both wet and dry systems. DFW installed 68 wet systems, one dry system and 2 electronic preaction systems in common areas such as the corridors, suites, offices, locker rooms and concourses.

Ultimate public venue

According to Joe Severino, DFW Fire Protection's purchasing manager, when choosing a waterflow detector for the fire sprinkler system, the company went with its standard, arsenal of System Sensor waterflow detectors.

System Sensor WFD series waterflow detectors are housed in a rugged, NEMA 4-rated enclosure. Designed for both indoor and outdoor use, the WFD series operates across a wide temperature range, from 32 degrees Fahrenheit to 120 degrees Fahrenheit. To simplify installation, the WFD series uses two conduit openings-one open, one knockout type-to permit easy attachment to the local alarm system. WFD products feature an adjustable mechanical retard. The retard mechanism and terminal block, which encloses two SPDT switches, are both field-replaceable.

The WFD series waterflow detectors are utilized to detect the flow of water through pipes. Models are designed for commercial pipe sizes from two to eight inches in diameter and for one-inch NPT connections used in residential or branch line signaling. The series provides two options for the retard mechanisms: one with a built-in, adjustable time delay and one that delivers an immediate alarm.

Sprinkler systems monitoring ensures continuous operation

The main goal of a sprinkler system is to provide a steady supply of fire extinguishing material that's ready to burst into action should a fire break out. A properly installed and maintained automatic fire sprinkler system can help save lives by dramatically reducing the heat, flames and smoke produced in a fire, allowing people time to evacuate.

Waterflow detectors, which are installed in fire alarm sprinkler systems, monitor the flow of water to sprinkler heads with a specially designed paddle. They are useful as security and safety tools because they eliminate the possibility of sprinkler malfunction. If a sprinkler head is activated and water begins to flow, for example, the waterflow detector will send a signal notifying the fire alarm control panel.

Vane or paddle type waterflow detectors are used to detect the flow of water in a wet pipe sprinkler system and to send an alarm signal. Waterflow detectors can be mounted to vertical upflow or horizontal-run distribution pipes in wet pipe sprinkler systems.

The detectors include a plastic vane or paddle, which installs through an opening in the wall of the distribution pipe. When the flow of water is greater than 10 gallons per minute, the vane or paddle deflects, which produces a switched output, usually after a preset time delay.

To minimize false alarms due to pressure surges or air trapped in the sprinkler system, a mechanical delay is often used to postpone switch activation. Often referred to as a retard, this delay takes the place of the previously mentioned retard chambers in wet pipe systems. If water flow decreases to four gallons per minute or below, the timing mechanism will reset to zero; delays do not accumulate. Time delays are adjustable from zero to 90 seconds.

Typically, waterflow detectors are equipped with dual SPDT (Form C) switches for activation of an alarm panel and alarm bell, or an A/V device. When a waterflow detector is connected to a listed sprinkler/fire alarm control panel, the initiating circuit must be non-silenceable. Waterflow detectors are designed to be installed in a variety of environments and are approved for both indoor and outdoor applications. U-bolt type waterflow detectors are designed primarily for use in commercial applications.

T-tap type waterflow detectors are also available and are primarily used in residential applications and branch line signaling in larger systems. The only differences between U-bolt and T-tap style waterflow detectors are the methods by which they attach to the pipe. T-tap style waterflow detectors also are available without a time delay mechanism.

Super Bowl fumble: seats unsafe

When it comes to adapting to building changes, fire and life safety goes beyond the building systems in place. The National Football League learned that lesson about a temporary seating section that was installed at the stadium to accommodate Super Bowl 2011 fans. Hours before the Green Bay Packers played the Pittsburgh Steelers about 1,250 temporary seats were deemed unsafe. The NFL scrambled to find new seats for about 850 people. The remaining 400 fans were forced to watch from standing-room locations around the stadium.

The events leading to the announcement show how fire and life safety goes beyond precautionary measures. In the process of getting a permit for the seating from the city of Arlington, several concerns were raised that needed to be corrected prior to the day of the event:

- Structural columns appeared to interrupt some aisle stairs.
- Some sets of plans did not have an engineer's seal or signature.
- Guardrails were not shown for stair landings.
- Handrails were not shown in some areas.
- Required headroom clearances were not shown.
- Information for stairways into and out of the seating areas was missing.

In addition, fire officials required proof that an engineer had signed off on the plans within two days, and they wanted firefighters assigned to oversee temporary seating sections for the safety of the people watching the game from those spots.

Undoubtedly, the temporary seating section snafu, which has been called a "horrible mistake," angered misplaced fans. Like it or not, safety standards are in place for a reason and life safety is always a core critical component to the protected premises.

Jackie Lorenty is the marketing manager, AMCO/Fire Sprinkler Business Unit, System Sensor U.S.