By Roy Pachecano
Today's building operations professionals and facility executives must confront the new realities affecting the built environment in the aftermath of 9/11. The question of upgrading current building codes in the face of the World Trade Center (WTC) collapse has touched off a debate in the design, construction, and real estate communities that will impact facility management operations across the country.
What follows is an identification of the code changes that are being presented for review and an analysis of what changes are likely to take place. It is supplemented with interviews and observations of several veterans from the field. (A list of references and contacts is cited at the end of the article.)
History And Public Opinion
Disasters spark change. Beginning in the late 1980s, two decades after the construction of the WTC, New York City seismologists and engineers lobbied the city to adopt seismic building codes because of its history of moderate seismic activity. Then in 1994, the Northridge Earthquake devastated the Los Angeles area, prompting California code officials to revise outdated seismic codes. This resulted in a national effort to introduce code changes in jurisdictions where seismic activity could occur. New York City followed suit in 1996.
One tragic historic example of heightened public concern cited by experts is found in another New York City disaster: the Triangle Shirtwaist fire of 1911. This horrible event claimed the lives of 146 young women, many who leapt to their deaths from the ninth story because the exit stairs were locked by the building owner. This event set off public outrage and led to the regulation of safety in the workplace. It also set a major precedent for more stringent building and fire codes concerning egress in tall buildings.
Since WWII, the trend in building has favored lightweight construction. While the WTC tower collapse was not entirely comparable to the B-25 bomber that flew into the Empire State Building in July 1949, certain lessons were gleaned from the resulting damage. That crash caused substantial interior damage to three upper floors of the New York landmark, but the actual building structure was not disabled or severely impaired.
One difference was the structural make-up of the tower. Older skyscrapers like the Empire State Building are held up by a complex network of steel beams wrapped in concrete, or in today's vernacular "hardened." The design limited the amount of open space on the floors, but also compartmentalized the floor to create barriers that could serve to impede the spread of fire.
Most experts agree that a reinforced concrete core offers greater fire protection than one made of steel beams and wall board. A concrete floor offers more fire resistance than steel if only because the fireproofing spray on steel tends to fall off over time as new tenants reconfigure spaces–especially in older, aging structures.
In an April 2, 2002 article entitled "U.S. Report On Trade Center Echoes Lessons Of Past Disasters," New York Times reporters Eric Lipton and James Glanz write, "‘With the old buildings, you know the building's going to hold,' said Neil P. Winberry, a retired New York fire captain. After the city fire code was changed in 1968, allowing a widespread shift from masonry fireproofing to a light, spray-on product, Winberry said, ‘we could not understand how this was going to work; we had no faith in it.'"
Lipton and Glanz conclude, "The fire and collapse of the World Trade Center last 9/11 in many ways stand alone, both in the terrifying attack and in the incomprehensible death toll. The first federal assessment of the trade center disaster...has made clear that there may have been no reasonable precautions that could have stopped the towers from collapsing once they were struck and huge fires broke out." Like the Empire State Building crash and the Triangle Shirtwaist factory fire, the WTC collapse will undoubtedly change the way high-rise structures will be built in the future.
Code Changes Pre-9/11
Those who advocate change are often building authorities and code administrators who seek to minimize loss of life and injury in building related emergencies. For these officials, public safety is a primary concern.
Organizations that make recommendations and write proposed changes to building codes–such as the American Society of Civil Engineers (ASCE) or the National Fire Protection Agency (NFPA)–are likely to have some success at amending current codes due to the climate surrounding the tragic events of 9/11. However, under traditional circumstances, the extent to which major code changes take place has depended largely on the following variables:
1. Public opinion: significant changes ultimately rely on the political process to make change take effect legally;
2. Public and private sectors: ultimate willingness of municipalities, agencies, corporations, and institutions to carry additional expenses related to code upgrades and retrofitting; and
3. Market forces: reality of building economically in light of new code mandates that may suppress development.
In the past, those who have been hesitant about change were generally building and property owners who had to pay for code-mandated building enhancements that could drastically affect rental rates and the marketability of their buildings. For these constituents, public safety was offset by cost.
Real estate companies and property owners are now contending with the growing number of occupants who are demanding building safety and security in the workplace. Concerned for loss of revenue caused by those who are drawn to more secure facilities, the real estate community has realized that building amenities that enhance security, transportation, and environmental safety may improve the bottom line.
As this issue went to press, numerous architects; mechanical, electrical, plumbing, and structural engineers; high-rise construction teams; fire experts; and hundreds of design professionals have been conferring in a crisis mode to feed valuable information and research data to government agencies [such as the Federal Emergency Management Agency (FEMA)].
Gregory Waugh, AIA, senior architect at Kohn Pedersen Fox (KPF), New York sees definite changes being considered in the design of high-rise structures. Several ideas include increasing the exit capacity for buildings with high-occupancy. In Waugh's opinion, a dedicated fireman's lift would ideally be located adjacent to egress stairs and refuge areas that would accelerate evacuation of building occupants in times of emergency.
KPF looks to the latest technology for ideas that are actually ahead of building codes. KPF's numerous overseas towers (and those in the planning stages) exceed even current U.S. building codes. In specifying more stringent safety measures, the designs emphasize: emergency egress, improved fire resistant materials, increased fire rated construction, enhanced elevator and hoistway design, and communications systems that include key command stations and safe area locations.
Jerome Scanlon, RA, veteran code consultant with New York, NY-based Charles Rizzo & Associates, believes more change will likely occur in the area of security–not construction and design. With security on the minds of many facility professionals, Scanlon has witnessed an increase in security-related building alterations filings at New York City's Department of Buildings, confirming in part that security issues are a top priority for many owners who recently filed for a building permit.
"Short of regulating materials and methods of construction in new buildings, it would be difficult to upgrade the current codes to defend against the type of attack that occurred on 9/11," says Scanlon.
Another advocate professing the lack of need to change current building codes is Roger Tooze, superintendent of buildings and grounds at New York's renowned Cooper Union for the Advancement of Science and Art. Tooze believes the building codes already in effect at the WTC saved many lives; potentially, the disaster could have been much worse.
"The building's structural system was able to span around the giant holes and redistribute the load of the building to the ground allowing an estimated 25,000 lives to be saved. In the aftermath of the WTC disaster, it is key that we continue [not only] to follow the existing laws and building regulations, but [also to] increase our awareness of our environment and security issues," Tooze concludes.
Since 9/11, building operators have restricted access to facilities, increased surveillance and foot patrols, and forged stronger ties with local communities. Future security measures may include a tighter control of public information, heightened occupant demand for security in buildings, and increased experimentation with new technology such as robotics to assist facility executives.
Many government controlled agencies are tightening their grip on access to public information, which can be considered vital to security. Reacting to reports that terrorist groups frequently teach recruits to scour public libraries and depositories for information about buildings, infrastructure, and transportation networks, city and state legislatures across the country are instituting bills that would broaden state subpoena power and seal public records when the public safety is believed at issue. In fact, the New York City Department of Buildings took such a step immediately after the attacks and closed off the records division of the city agency.
Codes Vs. Security
A cautious Joseph Gabriel of the New York Stock Exchange's facilities department anticipates possible conflicts caused by stricter codes and security issues. For example, new fire codes may call for increased emergency egress which is completely opposed to security measures which strive to close-off buildings.
Gabriel voices his concern and points out, "We need to be careful that we are not reacting to a far less frequent threat than fire. We as architects must be cognizant not to build bunkers but use the most sophisticated materials we can to maintain our environment and protect human life."
Operating efficiency may be diminished in order to increase security and flexibility. William Shaw, CEOE, head of operations at The Carlyle Hotel in New York, NY, underscores the increase in security issues confronting hotels in the city.
"From a hospitality view point, hotels must be ready for a whole range of events, so contingency planning is critical. Having a set of procedures in place is key to overcoming the initial chaos that surrounds a terrorist event," Shaw states. He feels the current codes are adequate, but stresses that people in general must become more sensitized to their environment and aware of their surroundings.
Codes Under Review
At a House Science Committee hearing on May 1, 2002, FEMA and ASCE (in conjunction with the National Institute of Standards and Technology, or NIST) released the results and recommendations of their investigation into the collapse of the WTC. The results of this report have confirmed the observations and conclusions of a preliminary report released in March regarding the structural and fire related performance of the WTC towers.
What was the initial key vulnerability in the WTC design? According to the Executive Summary of the WTC Building Performance Study, "...as the burning jet fuel spread across several floors of the buildings, it ignited much of the buildings' contents, causing simultaneous fires across several floors of both buildings. The heat output from these fires is estimated to have been comparable to the power produced by a large commercial power generating station. Over a period of many minutes, this heat induced additional stresses into the damaged structural frames while simultaneously softening and weakening these frames." In the 1960s, engineers could not have foreseen the awesome impact and force unleashed by 10,000 gallons of jet fuel on each 767 airplane.
Final results of the WTC Building Performance Study have sparked plans for a follow-up investigation and draft legislation. Engineering experts quickly endorsed a draft bill being circulated by House Science Committee Chairman Sherwood Boehlert (R-NY) and Rep. Anthony Weiner (D-NY) to remedy problems that arose during an investigation into the collapse of the WTC.
Glen Corbett, professor of Fire Science at John Jay College, endorsed the legislation, stating "In my over 20 years in the fire service, this is the most important legislation that would affect the study of disasters, including fires and other catastrophic events."
Stronger fire protection standards for commercial buildings may well result from ASCE's engineering analysis of the towers' collapse. However, the report "does not draw conclusions about whether even the best designed fire suppression system could have saved the buildings. The final report also points out that the structure's steel-tube design performed exceptionally well despite the impact of the airliners.
Conclusions By NIST
The primary goal of a longer-term study by NIST is to produce cost-effective options for retrofit design measures and guidance for existing facility executives and building owners. Three examples of remedial work that would be accomplished through its program are:
1. NIST would provide performance criteria for fireproofing materials. Current building design practice does not consider fire as a design condition. Instead, fire endurance ratings are prescribed in building codes using standard tests on individual components. The current testing standards are based on work carried out at NIST in the 1920s. They do not represent fire hazards in modern buildings.
2. NIST would provide the technical basis and guidance to prevent progressive collapse. This area of study refers to the containment of structural failure to prevent more damage and deaths resulting from a chain reaction that is disproportionate to the triggering event. The U.S. has not developed standards, codes, and practices to assess and reduce this vulnerability.
3. NIST intends to report ways of reducing the vulnerability of commercial and institutional buildings and facilities by utilizing state-of-the-art sensing and information management systems. Few facilities have electronic representations of building documents or models, and standards do not exist for such representations. Most are not protected against chemical, biological, and radiological threats. There are no standards or practices for civilian buildings.
The outcome of NIST's investigation and the final report released by FEMA will undoubtedly affect virtually every public and major commercial building design and construction project planned in the U.S. As public opinion, public/private sectors, and market forces converge to create a new set of standards, the inevitable changes to building codes will reflect the new realities affecting facility executives, property owners, developers, and design professionals.
It is doubtful, however, that new building codes will prevent real estate developers from attempting to finance and build tall buildings. The new challenge will be selling high-rise space that comes on the market now that some businesses are wary of such lofty spaces. Regardless of whether new codes and revised zoning configurations limit the heights of buildings, the real estate community is closely monitoring regulatory authorities to see what will take effect.
–Roy R. Pachecano, AIA
Pachecano serves as in-house architect/design consultant to the nationally recognized construction law firm of LePatner & Associates LLP. The New York City firm acts as business and legal advisors to the real estate, design, and construction communities.
• American National Standards Institute (ANSI), www.ansi.org
• American Society of Civil Engineers (ASCE), www.asce.org
• American Society of Testing Materials (ASTM), www.astm.org
• Building Officials and Code Administrators International (BOCA), www.bocai.org
• Federal Emergency Management Agency (FEMA), www.fema.gov
• International Conference of Building Code Officials (ICBO), www.icbo.org
• National Fire Prevention Association (NFPA), www.nfpa.org
• National Institute for Standards and Technology (NIST), www.nist.gov
• Society of Fire Protection Engineers (SFPE), www.sfpe.org
• Southern Building Code Congress International, Inc. (SBCCI), www.sbcci.org