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Codes
Under Fire
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California code officials to revise outdated seismic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 spacesespecially
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 codessuch
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.
Security Post-9/11
Jerome Scanlon, RA, veteran code consultant with
New York, NY-based Charles Rizzo & Associates, believes
more change will likely occur in the area of securitynot
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.
Resource List
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
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