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WASHINGTON,
D.C.— William Jeffrey, director of the
U.S. Commerce Department’s National Institute
of Standards and Technology (NIST), today
called on the organizations that develop
building and fire safety codes, standards
and practices— and the state and local
agencies that adopt them—to give immediate
and serious consideration to implementing
the recommendations from NIST’s
investigation of the fires and collapses
of New York City’s World Trade Center
(WTC) towers following the terrorist attacks
of Sept. 11, 2001.
The
final report from the most detailed examination
of a building failure ever conducted was
released today at a hearing of the House
Science Committee on the NIST investigation
at which Jeffrey testified. Featured in
the report are 30 recommendations designed
to improve the safety of tall buildings,
their occupants and first responders.
It is available online at http://wtc.nist.gov.
“I
have assigned top priority for NIST staff
to work vigorously with the building and
fire safety communities to assure there
is a complete understanding of the recommendations
and to provide needed technical assistance
in getting them implemented,” Jeffrey
told the committee.
Jeffrey
said that NIST believes its recommendations
are realistic, appropriate and achievable
within a reasonable period of time. However,
he cautioned that improvements would only
be realized if they are acted upon by
the appropriate organizations. To facilitate
this effort, NIST to date has:
- identified specific codes,
standards and practices affected by
each of the 30 recommendations in the
final WTC towers report;
- reached out to the organizations
responsible for making changes to expedite
consideration of and action on the recommendations
(for example, NIST held a major technical
conference on the recommendations in
September 2005 attended by over 200
people, including representatives from
all major standards and codes development
organizations); and
- awarded a contract to the non-profit
National Institute of Building Sciences
to turn many of the recommendations
into code language suitable for submission
of code change proposals to the two
national model code developers, the
National Fire Protection Association
and the International Code Council.
The
NIST recommendations released today are
contained within 43 separate reports (totaling
some 10,000 pages) that cover:
- specific improvements to
building standards, codes and practices;
- changes to, or the establishment
of, evacuation and emergency response
procedures; and
- research and other appropriate actions
needed to help prevent future building
failures.
Based
on nearly 500 comments received during
the six-week public review period following
the release of the draft WTC towers report
on June 23, 2005, the reports—including
some of the recommendations—were amended
and clarified. Both the complete set of
comments and the full version of the final
recommendations are available online at
http://wtc.nist.gov.
The
recommendations are divided into eight
groups and summarized as follows:
1)
Increased Structural Integrity:
The standards for estimating the load
effects of potential hazards (e.g., progressive
collapse, wind) and the design of structural
systems to mitigate the effects of those
hazards should be improved to enhance
structural integrity.
Among
the recommendations in this group are:
- nationwide adoption of standards
and codes to prevent progressive collapse;
- more reliable means of predicting
the potential for complex failures in
structures subjected to multiple hazards;
and
- nationally accepted standards for
wind tunnel testing of prototype structures
and estimating wind loads for tall buildings.
2)
Enhanced
Fire Resistance of Structures:
The procedures and practices used to ensure
the fire resistance of structures should
be enhanced by improving the technical
basis for construction classifications
and fire resistance ratings; improving
the technical basis for standard fire
resistance testing methods; using the
“structural frame” approach to fire resistance
ratings; and developing in-service performance
requirements and conformance criteria
for spray-applied fire resistive materials
(SFRMs, commonly
referred to as “fireproofing”).
Among
the recommendations in this group are:
- evaluating, and where needed,
improving, the technical basis for determining
appropriate construction classifications
and fire rating requirements—especially
for tall buildings—and making related
code changes now by considering a variety
of factors (including timely access
by emergency responders, full evacuation
of occupants and redundancy in fire protection
systems critical to structural safety);
- improving the century-old
standard for fire resistance testing
of building components, assemblies and
systems—including establishing a capability
for doing the improved testing under
realistic fire and load conditions;
and
- developing and implementing criteria,
test methods and standards for measuring
the in-service performance and as-installed
condition of “fireproofing.”
3) New Methods
for Fire Resistance Design of Structures:
The procedures and practices used in the
design of structures for fire resistance
should be enhanced by requiring an objective
that uncontrolled fires result in burnout
without partial or global (total) collapse.
Performance-based methods are an alternative
to prescriptive design methods. This effort
should include: (1) the development and
evaluation of new fire resistive coating
materials and technologies, and (2) the
evaluation of the fire performance of
conventional and high-performance structural
materials (such as fire-resistant steels
and concretes). Technical and standards
barriers to the introduction of new materials
and technologies should be eliminated.
4)
Active Fire Protection: Active
fire protection systems (i.e., sprinklers,
standpipes/hoses, fire alarms and smoke
management systems) should be enhanced
through improvements to design, performance,
reliability and redundancy of such systems.
Among
the recommendations in this group are:
- enhancing fire protection
systems to provide redundancy and accommodate
the higher risks associated with tall
buildings;
- developing advanced fire
alarms and communications systems that
provide continuous, reliable and accurate
information on life safety conditions;
and
- developing and requiring real-time
secure transmission of data from fire
alarm and other monitored building systems
for use by emergency responders at any
location, and storage of that data off-site
or in a black box.
5)
Improved Building Evacuation:
The process of evacuating a building should
be improved to include system designs
that facilitate safe and rapid egress;
methods for ensuring clear and timely
emergency communications to occupants;
better occupant preparedness for evacuation
during emergencies; and incorporation
of appropriate egress technologies.
Among
the recommendations in this group are:
- improving occupant preparedness
for building evacuations through joint
and nationwide public education and
training campaigns;
- designing tall buildings
to accommodate timely full building
evacuation of occupants if needed—including
stairwell capacity and stair discharge
door width that accommodates counterflow
due to access by emergency responders;
- maximizing the remoteness
of egress components (i.e. stairs, elevators)
without making them hard to reach;
- using pagers and cell phones
for broadcast warning systems and Community
Emergency Alert Networks; and
- evaluating for future use such current
and next-generation evacuation technologies
as protected/hardened elevators, exterior
escape systems and stairwell descent
devices.
6)
Improved Emergency Response: Technologies
and procedures for emergency response
should be improved to enable better access
to buildings, response operations, emergency
communications, and command and control
in large-scale emergencies.
Among
the recommendations in this group are:
- installing fire-protected
and structurally hardened elevators
to improve emergency response activities,
the evacuation of mobility impaired
occupants—and preferably, all occupants—in
tall buildings;
- installing, inspecting and
testing emergency communications systems,
radio communications and associated
operating protocols to ensure that the
systems and their protocols will function
in challenging radio frequency propagation
environments and large-scale operations,
and can be used to track emergency responders
within a building; and
- developing and implementing codes
and protocols for ensuring effective
and uninterrupted operation of the command
and control system in large-scale building
emergencies.
7)
Improved Procedures and Practices:
The procedures and practices used in the
design, construction, maintenance and
operation of buildings should be improved
to include encouraging code compliance
by non-governmental and quasi-governmental
entities; adoption and application of
egress and sprinkler requirements in codes
for existing buildings; and retention
and availability of building documents
over the life of a building.
8)
Education and Training: The professional
skills of building and fire safety professionals
should be upgraded through a national
education and training effort for fire
protection engineers, structural engineers
and architects. The skills of building
regulatory and fire service personnel
also should be upgraded to provide sufficient
understanding of what is needed to conduct
the review, inspection and approval tasks
for which they are responsible.
Along
with strongly urging that immediate and
serious consideration be given to these
recommendations by the building and fire
safety communities, NIST also advocates
that building owners and public officials
evaluate the safety implications of these
recommendations to their existing inventory
of buildings; and take the steps necessary
to mitigate any unwarranted risks without
waiting for changes to occur in codes,
standards and practices. NIST further
urges state and local agencies to rigorously
enforce building codes and standards since
such enforcement is critical to ensure
the expected level of safety.
NIST
will establish a Web-based system with
information on the status of its WTC recommendations
that will be available to the public so
that progress in implementing them can
be tracked.
NIST’s investigation of the WTC towers
fires and collapses was conducted under
the National Construction Safety Team
(NCST) Act. The act gives NIST the authority
for conducting fact-finding investigations
of building-related failures that result
in substantial loss of life. NIST has
no regulatory authority under the NCST
Act.
The
NCST Act also states that no part of any
report resulting from a NIST investigation
into a structural failure or from an investigation
under the act may be used in any suit
or action for damages arising out of any
matter mentioned in the report.
NIST's mission is to promote U.S. innovation and industrial competitiveness
by advancing measurement science, standards,
and technology—in ways that enhance economic
security and improve our quality of life.
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