NFPA Journal - July/August 2012 - (Page 66)

STATUE OF LIBERTY Protection of Historic Structures, which was developed to address precisely this type of project. NFPA 914’s process is designed to identify normal solutions that don’t work for historic buildings and to replace them with innovative approaches—“close-to” code design, equivalencies, management operational controls, and more—that maintain a structure’s historic fabric while also achieving fire safety goals. Necessary adjustments The first phase of improvements was to the original double-helical stairs that spiral within the statue. Rather than replace the stairs, which did not comply with code-required riser THE “MEANS OF EGRESS” CHAPTER IN NFPA 101 ESTABLISHES THE RANGE OF PROVISIONS NEEDED FOR SUCH “SMOKEPROOF ENCLOSURES.” heights, tread depths, and headroom measurements, contractors installed handrails and guardrails for added safety. (Chapter 7 of NFPA 101, which outlines means of egress requirements, includes a “guards and handrails” section for new and existing stairs.) The upgrades now permit visitors to safely descend both stairs in an emergency. Protective glass sheets were also placed in certain areas near the stairs where the handrails and guardrails couldn’t go, thus serving the same purpose as guardrails and preventing visitors from touching aspects of the statue’s historic framework. Contractors secured the glass using specially designed clamps in an effort to avoid drilling into the structure’s internal framework, which had been designed by Gustave Eiffel. The 11-week project was completed in July 2009. The NPS once again reopened the monument to the public, but limited the number of visitors to 30 at a time: 10 people in the crown’s observation platform, and 10 apiece on each of the statue’s staircases. “This was a management strategy recommended by Hughes Associates to minimize exposure of visitors and NPS staff to risks while in the statue,” says Duffy. “Previous to the planned re-opening of the monument this fall, the NPS will re-evaluate how visitors are managed to maintain safety and make appropriate changes.” Immediately following the 125th anniversary of Lady Liberty’s commemoration last October, the NPS once again shut down access to the monument to begin the next phase of fire and life safety upgrades. (Liberty Island, the nearly 15-acre [six-hectare] plot of land in New York Harbor where the statue is located, has remained open to visitors during the project. The island attracts about 3.5 million visitors a year.) Before work could begin on the next phase of life safety upgrades, NPS had to secure the funding, conduct an environmental assessment, and complete designs for new elevators and improved egress routes that didn’t compromise the structural and historical integrity of the monument. NPS anticipates the completion of all upgrades, including restroom renovations and a new HVAC system, by the end of the year. One key element of the secondround improvements was the main elevator, which is housed in the pedestal and transports passengers to a level below the pedestal observation platform. (From there, visitors take a supplemental lift or stairs to the platform.) The problem was that the existing elevator—a freestanding glass model with no enclosure—did not meet the necessary code requirements for size. Creating a larger elevator shaft at the same location would have impacted the pedestal’s structural beams, so contractors relocated the shaft to another portion of the pedestal’s interior. The demolition of nearly 1,300 cubic feet [nearly 37 cubic meters] of concrete—a modest amount that was approved by SHPO, notes Duffy—helped make way for the new elevator core as well as two new code-compliant staircases configured around the core that lead to the observation platform. The freestanding elevator was removed. Those new staircases include pressurization systems that bring in outside air to minimize the presence of smoke during a fire event. “Theoretically, if the doors are closed, the pressurization prevents smoke from entering the stairs,” says Ferreira. “Pressurization systems are required for stairwells in new high-rise buildings.” The “means of egress” chapter in NFPA 101 establishes the range of provisions needed for such “smokeproof enclosures.” For example, access to and discharge from the enclosures, as well as pressurization levels needed to keep the environment clear of smoke from a fire, must be balanced against the opening force of the enclosure doors. The code also requires emergency power to the mechanical fan system. Additionally, pressurization of high-rise exit stair enclosures is a requirement listed in the high-rise buildings chapter of NFPA 5000, Building Construction and Safety Code®. Also underway is the development of a “supplemental lift” to transport visitors who may have mobility impairments from the main elevator’s highest level in the pedestal to the pedestal’s observation platform, as well as the replacement of the statue’s emergency elevator, which travels from the pedestal observation level to a floor level near the statue’s shoulder. Workers are also upgrading the pedestal’s fire protection 66 NFPA JOURNAL JULY/AUGUST 2012

Table of Contents for the Digital Edition of NFPA Journal - July/August 2012

NFPA Journal - July/august 2012
Contents
First Word
Mail Call
In a Flash
Perspectives
Firewatch
Research
Heads Up
Structural Ops
In Compliance
Buzzwords
Outreach
Electrical Safety
Wildfire Watch
Fenway at 100
Crowning Achievement
Safety at Center Stage
Firefighter Fatalities in the United States, 2011
What’s Hot
Looking Back

NFPA Journal - July/August 2012