// re: buildings in emergencies. see URL for
// links to resources mentioned in the article.
High-rises remain vulnerable after 9/11
Wed Sep 25, 7:21 AM ET
Patrick O'Driscoll USA TODAY
http://story.news.yahoo.com/news?tmpl=story2&cid=676&ncid=716&e=18&u=/
usatoday/20020925/ts_usatoday/4478793
CHICAGO -- More than a year after terrorists destroyed two of the
tallest skyscrapers in the world, few physical or structural changes
have been made to strengthen tens of thousands of other high-rises in
America.
Cities, developers and building owners have focused on safety measures
such as evacuating people more quickly, but the nation's high-rises
remain largely as vulnerable to catastrophic attack as they were on
Sept. 11, 2001.
Major changes in design and construction that would retard fire and
help evacuations -- two critical issues in the disaster at New York's
World Trade Center -- won't show up soon, if at all, as requirements
for new tall buildings. That's because revisions in building codes,
which are controlled by state and local governments, could take years
to draft. Major physical alterations of the same sort to existing
high-rises might be impossible, impractical or prohibitively expensive.
Of course, none of the nation's tall buildings was designed to survive
what was unthinkable until the twin towers were attacked: Hijacked
jetliners, loaded with fuel, intentionally exploding into them at 500
mph, igniting 2,000-degree fires that twist and melt the structure into
catastrophic collapse.
''After Pearl Harbor, people didn't say, 'Ships are unsafe (so) you
have to build unsinkable ships,' '' says David Maola, executive
director of the Council on Tall Buildings and Urban Habitat, which
promotes better design and construction of high-rises. ''No, you have
to keep airplanes away from ships -- and you have to keep airplanes
away from buildings.''
An initial investigation completed last spring by civil engineers and
federal emergency managers ( www.fema.gov/library/wtcstudy.shtm)
explored likely causes of the Trade Center collapse. Investigators
found that the twin towers withstood the initial impacts of the two
airliners, but centrally clustered escape stairwells and fire sprinkler
supply lines, which were encased in lightweight walls, were knocked out
instantly. Fire was a bigger factor: The impact and flying debris
probably jarred loose spray-on fireproofing from beams and trusses both
in the twin towers and in a neighboring high-rise that also collapsed.
The structural steel was softened to the point of collapse by intense
blazes that were fed and spread by the jets' aviation fuel.
Even though building code changes may be years away, some of those
early conclusions are beginning to influence the design and
construction of high-rise projects. Among measures being added or
considered:
* Locating stairwells farther apart, widening them for faster
evacuation and encasing them in concrete.
* Strengthening connections and joints in structural steel framing.
* Using fireproofing that clings better to beams and girders, and
applying it more thickly.
* Installing backup water supplies for fire sprinkler systems.
Some high-rises thought to be vulnerable to terrorism, either as
targets or as neighbors of other high-profile buildings, also are being
''hardened'' against bombs and other attacks with structural
reinforcements, shatterproof windows and other measures. New York's
59-story Citigroup Center is undergoing work to strengthen a leg-like
support column thought to be exposed to potential attack where it faces
busy 53rd Street in midtown Manhattan.
New York set up a building code task force to examine many issues after
the twin towers' collapse. It is expected to report its findings in
December.
But most local governments are not rushing to revise codes and
procedures. Nor will the federal government step in to order changes.
Except for federal jurisdiction in areas such as workplace safety and
accessibility for the disabled, codes for building design, construction
and operation remain local or state responsibilities.
Focus on safety
Just as aviation security was tightened to unprecedented levels in the
hijackings' aftermath, so too was security in tall buildings: More
guards and cameras, metal and X-ray screening, more elaborate
access-control systems, concrete barricades on sidewalks, even
bomb-sniffing dogs at loading docks. Now, safety measures are also
under review. Skyscrapers in some cities are providing fire and rescue
agencies with critical details about their layout and systems so crews
can respond more quickly and safely.
Here in Chicago, an ordinance since the terror attacks requires the
city's 56 tallest buildings to provide such data twice a year on CD-ROM
so fire commanders can check the data instantly via computer at the
scene.
Other priorities:
* Evacuation. From New York to Honolulu, city fire and emergency
agencies are rethinking how, when, whether and whom to evacuate. The
traditional philosophy has been to keep high-rise occupants at their
desks unless their floor or one near it is at immediate risk. But on
Sept. 11, workers who fled the upper floors of the World Trade Center's
south tower immediately after seeing the first jet hit the other tower
were more likely to survive. Those who obeyed announcements to stay put
or go back did not, once the second airliner had struck and crippled
their building 16 minutes later.
Today, many tenants ''self-evacuate'' in any high-rise alarm,
regardless of what building managers tell them. In some cases since
Sept. 11, authorities in New York, Boston, Los Angeles and elsewhere
have cleared out entire buildings in emergencies. But safety experts
still caution against wholesale evacuations: ''There's no sense in
emptying a building with 7,000 or 8,000 people in it if you have a
garbage can on fire,'' says Robert Solomon of the National Fire
Protection Association, which drafts safety and fire standards.
* Drills and alarms. From Chicago's 110-story Sears Tower to New York's
50-story W.R. Grace Building, owners and managers voluntarily perform
more frequent fire and escape drills, sometimes at the urging of
tenants who once considered them a nuisance. Most cities don't require
extensive or buildingwide drills, but that's changing, too. This month,
Pittsburgh's mayor proposed requiring twice-yearly drills in the city's
300 high-rises. In Los Angeles, the city attorney has proposed
mandatory evacuation tests and emergency plans for all high-rises.
Some workers, companies and residents even insist on practice
evacuations all the way to the ground, not just to exit doors or down a
floor or two as before. ''Nobody trusts the structural integrity of
buildings any more to save them or protect them,'' says Judith
Telingator, who lives in Chicago's One Magnificent Mile, a 57-story
office and condominium tower whose occupants now drill monthly, floor
by floor. ''Now we're much more confident about what to do.''
* Stairs. Some high-rises are upgrading signs and equipment in exit
stairwells, the only escape route in most emergencies. In Chicago, the
65-story 311 South Wacker Drive building installed glow-in-the-dark
signs, arrows and striping to guide evacuees in case backup lights
fail. Experts also are scrutinizing the standard 44-inch stair width
for future high-rises, a norm that some critics say is too narrow to
accommodate occupants fleeing downstairs and firefighters going up. The
evacuation of an estimated 50,000 people after the 1993 bombing at the
World Trade Center took nearly four hours, precious time that Sept. 11
victims never had. But lighting and sign improvements made after the
1993 attack did help evacuees nine years later. So did having three
evacuation stairs in each tower (one of them 56 inches wide) rather
than the two required by building codes.
* Equipment. Some high-rises, including the Sears Tower, are equipping
stairwells with two-wheeled escape chairs to help carry disabled or
injured occupants. Because of tragic 9/11 stories of doomed
firefighters overburdened with gear and out of radio contact, Chicago
and other cities are reviewing emergency communications and requiring
or recommending that skyscrapers install lockers or closets with hoses,
axes and oxygen tanks on upper floors so firefighters don't have to
carry them. Also gaining renewed interest: ''evac kits,'' often in red
fanny packs, that workers keep at their desks with escape essentials
such as glow sticks and water.
''It always takes disaster to bring about change,'' says Curtis Massey,
a high-rise safety consultant from Virginia Beach. A former
firefighter, Massey has written quick-read, color guides for fire
departments to hundreds of skyscrapers, including the tallest in 30 of
the nation's 34 largest cities.
Thousands of buildings
As a practical matter, only a few major skyscrapers rise to ''icon''
status and thus qualify as potential targets of terror. But the fiery
deaths of so many occupants and rescuers -- 2,803 victims in the New
York towers -- set off alarms about safety against any disaster in
buildings with floors beyond the reach of conventional fire ladders.
That means anything taller than about 75 feet, a common definition of
''high-rise.''
Skyscrapers.com, which compiles building statistics worldwide, uses a
higher definition: At least 115 feet or 12 stories tall. By either
yardstick, thousands of buildings (more than 16,500 nationally and at
least 4,448 in New York City alone, by Skyscrapers.com's count) face
potential review.
Safety consultants are doing brisk business since 9/11.
Disaster-planner Massey has taken on 40 to 50 more buildings, and three
major property management firms ordered his guides for all their New
York buildings.
Engineers who specialize in armoring embassies and other potential
terror targets now do similar jobs for high-rises and other commercial
structures.
''Our existing clients are coming back and saying, 'Do I have something
to worry about?' '' says Robert Underwood, vice president of facilities
security for Carter & Burgess Inc., a design and engineering firm based
in Fort Worth.
''It's not for everybody,'' says Tod Rittenhouse, a blast-resistance
expert for New York-based Weidlinger Associates Inc., whose clients
often seek protection against hits on nearby targets such as federal
buildings or foreign consulates.
Even safety-minded investors have jumped in to market an array of
evacuation ideas -- from a high-tech hovering rescue platform to rescue
slides and quick-pop personal parachutes.
Professional groups also are pushing safety.
The Council on Tall Buildings and Urban Habitat ( www.ctbuh.org) has
published twin guidebooks since Sept. 11 -- one on recommended safety
enhancements for building owners and designers, the other to help
people who live and work in high-rises assess how safe they are. The
National Fire Protection Association ( www.nfpa.org) is holding one-day
seminars this fall in 19 cities from California to Florida to help
high-rise managers draft emergency plans.
The Skyscraper Safety Campaign ( www.skyscrapersafety.org), founded by
families of Trade Center victims, advocates numerous code reforms in
New York and pushes for a more critical probe of how the city handled
the disaster.
Industry groups from cement and steel manufacturers to engineering and
architectural associations help draft model codes that states, cities,
counties and townships adopt or modify for local needs. If dramatic
design or construction flaws are found in disasters such as major fires
and building collapses, ''the model code system can react responsibly
and quickly -- within a year -- to identify a solution,'' says Paul
Heilstedt, chief executive officer of Building Officials and Code
Administrators International, a trade group. But he says ''the jury's
still out'' regarding the World Trade Center.
''People may be impatient, but the studies aren't done yet,'' adds
Jonathan Barnett, a fire-engineering professor at Worcester (Mass.)
Polytechnic Institute.
Last month, the federal government's National Institute of Standards
and Technology (NIST) began a two-year, $23 million study of the
towers' collapse. Its findings could lead to tougher building and
safety codes for tall buildings. But they would be recommendations, not
edicts.
The same goes for an initial study by the Federal Emergency Management
Agency ( news - web sites) and the American Society of Civil Engineers,
in which Barnett participated. Among other things, that report
suggested constructing emergency stairways farther apart and
''hardening'' them to resist outside impacts.
Safety vs. livability
When they do come, code changes could cost developers and owners
millions of dollars in added expense for constructing buildings or
adding safety improvements to older ones.
''You can make a building that's fireproof and airplane-proof,'' says
Larry Soehren, president of Building Owners and Managers Association
International ( www.boma.org), the industry's trade group. ''But
nobody's going to want to live or work in it'' because it would be a
windowless concrete bunker, not a soaring architectural gem. ''Let's do
science and research first.''
In New York, the building-code task force is considering a proposal
that fire safety directors recommended more than 25 years ago:
Mandatory fire sprinklers in all older high-rises, a requirement only
for structures built since the 1970s. Many older buildings have
gradually been retrofitted, but hundreds have not.
Also under review are design tradeoffs that came with the advent of
sprinklers as the principal tool against high-rise fire. Stairwells and
building cores, once walled with concrete or masonry, went to lighter,
fire-resistant drywall after sprinklers became common. But in the Trade
Center attacks, the jets sliced easily through that lightweight
construction, fatally severing the towers' central cores of elevators,
stairs and water lines to the sprinklers.
Improved fireproofing is another area of scrutiny. ''There already
exist some materials that will stick better,'' says Gene Corley, a
Chicago structural engineer who led the initial Trade Center study.
''Nothing is foolproof, of course, but you also have to look at the
safety of high-rise buildings in the last 100 years. They are extremely
safe buildings.''
In normal conditions, anyway. But after 9/11, almost every aspect of
high-rise safety is under scrutiny. ''I'm calling for reform, reform,
reform,'' says Sally Regenhard of the Skyscraper Safety Campaign, whose
firefighter son, Christian, died in the Trade Center collapse. ''We
have to legislate so that economic interests and greed do not take
precedence over the sanctity and safety of human life.''
http://story.news.yahoo.com/news?tmpl=story2&cid=676&ncid=716&e=18&u=/
usatoday/20020925/ts_usatoday/4478793
// links to resources mentioned in the article.
High-rises remain vulnerable after 9/11
Wed Sep 25, 7:21 AM ET
Patrick O'Driscoll USA TODAY
http://story.news.yahoo.com/news?tmpl=story2&cid=676&ncid=716&e=18&u=/
usatoday/20020925/ts_usatoday/4478793
CHICAGO -- More than a year after terrorists destroyed two of the
tallest skyscrapers in the world, few physical or structural changes
have been made to strengthen tens of thousands of other high-rises in
America.
Cities, developers and building owners have focused on safety measures
such as evacuating people more quickly, but the nation's high-rises
remain largely as vulnerable to catastrophic attack as they were on
Sept. 11, 2001.
Major changes in design and construction that would retard fire and
help evacuations -- two critical issues in the disaster at New York's
World Trade Center -- won't show up soon, if at all, as requirements
for new tall buildings. That's because revisions in building codes,
which are controlled by state and local governments, could take years
to draft. Major physical alterations of the same sort to existing
high-rises might be impossible, impractical or prohibitively expensive.
Of course, none of the nation's tall buildings was designed to survive
what was unthinkable until the twin towers were attacked: Hijacked
jetliners, loaded with fuel, intentionally exploding into them at 500
mph, igniting 2,000-degree fires that twist and melt the structure into
catastrophic collapse.
''After Pearl Harbor, people didn't say, 'Ships are unsafe (so) you
have to build unsinkable ships,' '' says David Maola, executive
director of the Council on Tall Buildings and Urban Habitat, which
promotes better design and construction of high-rises. ''No, you have
to keep airplanes away from ships -- and you have to keep airplanes
away from buildings.''
An initial investigation completed last spring by civil engineers and
federal emergency managers ( www.fema.gov/library/wtcstudy.shtm)
explored likely causes of the Trade Center collapse. Investigators
found that the twin towers withstood the initial impacts of the two
airliners, but centrally clustered escape stairwells and fire sprinkler
supply lines, which were encased in lightweight walls, were knocked out
instantly. Fire was a bigger factor: The impact and flying debris
probably jarred loose spray-on fireproofing from beams and trusses both
in the twin towers and in a neighboring high-rise that also collapsed.
The structural steel was softened to the point of collapse by intense
blazes that were fed and spread by the jets' aviation fuel.
Even though building code changes may be years away, some of those
early conclusions are beginning to influence the design and
construction of high-rise projects. Among measures being added or
considered:
* Locating stairwells farther apart, widening them for faster
evacuation and encasing them in concrete.
* Strengthening connections and joints in structural steel framing.
* Using fireproofing that clings better to beams and girders, and
applying it more thickly.
* Installing backup water supplies for fire sprinkler systems.
Some high-rises thought to be vulnerable to terrorism, either as
targets or as neighbors of other high-profile buildings, also are being
''hardened'' against bombs and other attacks with structural
reinforcements, shatterproof windows and other measures. New York's
59-story Citigroup Center is undergoing work to strengthen a leg-like
support column thought to be exposed to potential attack where it faces
busy 53rd Street in midtown Manhattan.
New York set up a building code task force to examine many issues after
the twin towers' collapse. It is expected to report its findings in
December.
But most local governments are not rushing to revise codes and
procedures. Nor will the federal government step in to order changes.
Except for federal jurisdiction in areas such as workplace safety and
accessibility for the disabled, codes for building design, construction
and operation remain local or state responsibilities.
Focus on safety
Just as aviation security was tightened to unprecedented levels in the
hijackings' aftermath, so too was security in tall buildings: More
guards and cameras, metal and X-ray screening, more elaborate
access-control systems, concrete barricades on sidewalks, even
bomb-sniffing dogs at loading docks. Now, safety measures are also
under review. Skyscrapers in some cities are providing fire and rescue
agencies with critical details about their layout and systems so crews
can respond more quickly and safely.
Here in Chicago, an ordinance since the terror attacks requires the
city's 56 tallest buildings to provide such data twice a year on CD-ROM
so fire commanders can check the data instantly via computer at the
scene.
Other priorities:
* Evacuation. From New York to Honolulu, city fire and emergency
agencies are rethinking how, when, whether and whom to evacuate. The
traditional philosophy has been to keep high-rise occupants at their
desks unless their floor or one near it is at immediate risk. But on
Sept. 11, workers who fled the upper floors of the World Trade Center's
south tower immediately after seeing the first jet hit the other tower
were more likely to survive. Those who obeyed announcements to stay put
or go back did not, once the second airliner had struck and crippled
their building 16 minutes later.
Today, many tenants ''self-evacuate'' in any high-rise alarm,
regardless of what building managers tell them. In some cases since
Sept. 11, authorities in New York, Boston, Los Angeles and elsewhere
have cleared out entire buildings in emergencies. But safety experts
still caution against wholesale evacuations: ''There's no sense in
emptying a building with 7,000 or 8,000 people in it if you have a
garbage can on fire,'' says Robert Solomon of the National Fire
Protection Association, which drafts safety and fire standards.
* Drills and alarms. From Chicago's 110-story Sears Tower to New York's
50-story W.R. Grace Building, owners and managers voluntarily perform
more frequent fire and escape drills, sometimes at the urging of
tenants who once considered them a nuisance. Most cities don't require
extensive or buildingwide drills, but that's changing, too. This month,
Pittsburgh's mayor proposed requiring twice-yearly drills in the city's
300 high-rises. In Los Angeles, the city attorney has proposed
mandatory evacuation tests and emergency plans for all high-rises.
Some workers, companies and residents even insist on practice
evacuations all the way to the ground, not just to exit doors or down a
floor or two as before. ''Nobody trusts the structural integrity of
buildings any more to save them or protect them,'' says Judith
Telingator, who lives in Chicago's One Magnificent Mile, a 57-story
office and condominium tower whose occupants now drill monthly, floor
by floor. ''Now we're much more confident about what to do.''
* Stairs. Some high-rises are upgrading signs and equipment in exit
stairwells, the only escape route in most emergencies. In Chicago, the
65-story 311 South Wacker Drive building installed glow-in-the-dark
signs, arrows and striping to guide evacuees in case backup lights
fail. Experts also are scrutinizing the standard 44-inch stair width
for future high-rises, a norm that some critics say is too narrow to
accommodate occupants fleeing downstairs and firefighters going up. The
evacuation of an estimated 50,000 people after the 1993 bombing at the
World Trade Center took nearly four hours, precious time that Sept. 11
victims never had. But lighting and sign improvements made after the
1993 attack did help evacuees nine years later. So did having three
evacuation stairs in each tower (one of them 56 inches wide) rather
than the two required by building codes.
* Equipment. Some high-rises, including the Sears Tower, are equipping
stairwells with two-wheeled escape chairs to help carry disabled or
injured occupants. Because of tragic 9/11 stories of doomed
firefighters overburdened with gear and out of radio contact, Chicago
and other cities are reviewing emergency communications and requiring
or recommending that skyscrapers install lockers or closets with hoses,
axes and oxygen tanks on upper floors so firefighters don't have to
carry them. Also gaining renewed interest: ''evac kits,'' often in red
fanny packs, that workers keep at their desks with escape essentials
such as glow sticks and water.
''It always takes disaster to bring about change,'' says Curtis Massey,
a high-rise safety consultant from Virginia Beach. A former
firefighter, Massey has written quick-read, color guides for fire
departments to hundreds of skyscrapers, including the tallest in 30 of
the nation's 34 largest cities.
Thousands of buildings
As a practical matter, only a few major skyscrapers rise to ''icon''
status and thus qualify as potential targets of terror. But the fiery
deaths of so many occupants and rescuers -- 2,803 victims in the New
York towers -- set off alarms about safety against any disaster in
buildings with floors beyond the reach of conventional fire ladders.
That means anything taller than about 75 feet, a common definition of
''high-rise.''
Skyscrapers.com, which compiles building statistics worldwide, uses a
higher definition: At least 115 feet or 12 stories tall. By either
yardstick, thousands of buildings (more than 16,500 nationally and at
least 4,448 in New York City alone, by Skyscrapers.com's count) face
potential review.
Safety consultants are doing brisk business since 9/11.
Disaster-planner Massey has taken on 40 to 50 more buildings, and three
major property management firms ordered his guides for all their New
York buildings.
Engineers who specialize in armoring embassies and other potential
terror targets now do similar jobs for high-rises and other commercial
structures.
''Our existing clients are coming back and saying, 'Do I have something
to worry about?' '' says Robert Underwood, vice president of facilities
security for Carter & Burgess Inc., a design and engineering firm based
in Fort Worth.
''It's not for everybody,'' says Tod Rittenhouse, a blast-resistance
expert for New York-based Weidlinger Associates Inc., whose clients
often seek protection against hits on nearby targets such as federal
buildings or foreign consulates.
Even safety-minded investors have jumped in to market an array of
evacuation ideas -- from a high-tech hovering rescue platform to rescue
slides and quick-pop personal parachutes.
Professional groups also are pushing safety.
The Council on Tall Buildings and Urban Habitat ( www.ctbuh.org) has
published twin guidebooks since Sept. 11 -- one on recommended safety
enhancements for building owners and designers, the other to help
people who live and work in high-rises assess how safe they are. The
National Fire Protection Association ( www.nfpa.org) is holding one-day
seminars this fall in 19 cities from California to Florida to help
high-rise managers draft emergency plans.
The Skyscraper Safety Campaign ( www.skyscrapersafety.org), founded by
families of Trade Center victims, advocates numerous code reforms in
New York and pushes for a more critical probe of how the city handled
the disaster.
Industry groups from cement and steel manufacturers to engineering and
architectural associations help draft model codes that states, cities,
counties and townships adopt or modify for local needs. If dramatic
design or construction flaws are found in disasters such as major fires
and building collapses, ''the model code system can react responsibly
and quickly -- within a year -- to identify a solution,'' says Paul
Heilstedt, chief executive officer of Building Officials and Code
Administrators International, a trade group. But he says ''the jury's
still out'' regarding the World Trade Center.
''People may be impatient, but the studies aren't done yet,'' adds
Jonathan Barnett, a fire-engineering professor at Worcester (Mass.)
Polytechnic Institute.
Last month, the federal government's National Institute of Standards
and Technology (NIST) began a two-year, $23 million study of the
towers' collapse. Its findings could lead to tougher building and
safety codes for tall buildings. But they would be recommendations, not
edicts.
The same goes for an initial study by the Federal Emergency Management
Agency ( news - web sites) and the American Society of Civil Engineers,
in which Barnett participated. Among other things, that report
suggested constructing emergency stairways farther apart and
''hardening'' them to resist outside impacts.
Safety vs. livability
When they do come, code changes could cost developers and owners
millions of dollars in added expense for constructing buildings or
adding safety improvements to older ones.
''You can make a building that's fireproof and airplane-proof,'' says
Larry Soehren, president of Building Owners and Managers Association
International ( www.boma.org), the industry's trade group. ''But
nobody's going to want to live or work in it'' because it would be a
windowless concrete bunker, not a soaring architectural gem. ''Let's do
science and research first.''
In New York, the building-code task force is considering a proposal
that fire safety directors recommended more than 25 years ago:
Mandatory fire sprinklers in all older high-rises, a requirement only
for structures built since the 1970s. Many older buildings have
gradually been retrofitted, but hundreds have not.
Also under review are design tradeoffs that came with the advent of
sprinklers as the principal tool against high-rise fire. Stairwells and
building cores, once walled with concrete or masonry, went to lighter,
fire-resistant drywall after sprinklers became common. But in the Trade
Center attacks, the jets sliced easily through that lightweight
construction, fatally severing the towers' central cores of elevators,
stairs and water lines to the sprinklers.
Improved fireproofing is another area of scrutiny. ''There already
exist some materials that will stick better,'' says Gene Corley, a
Chicago structural engineer who led the initial Trade Center study.
''Nothing is foolproof, of course, but you also have to look at the
safety of high-rise buildings in the last 100 years. They are extremely
safe buildings.''
In normal conditions, anyway. But after 9/11, almost every aspect of
high-rise safety is under scrutiny. ''I'm calling for reform, reform,
reform,'' says Sally Regenhard of the Skyscraper Safety Campaign, whose
firefighter son, Christian, died in the Trade Center collapse. ''We
have to legislate so that economic interests and greed do not take
precedence over the sanctity and safety of human life.''
http://story.news.yahoo.com/news?tmpl=story2&cid=676&ncid=716&e=18&u=/
usatoday/20020925/ts_usatoday/4478793