By Arthur Scheuerman Battalion Chief FDNY Retired, Former Deputy Chief Instructor Nassau County Fire Training Academy.

An analysis of the cause of the collapse of the WTC Towers. Possible lessons to be learned to improve high-rise building life safety. Feb. 13, 2002

To enter the debate as to whether the plane crashes or the resultant fires caused the collapse of World Trade Center Towers 1 and 2, I would like to weigh in on the side of the fires. These buildings were designed to take the impacts of a large plane crashes, and I doubt whether either building would have collapsed and whether multitudes of people would have been trapped above the crash floors except for the fire, smoke and heat. Apparently the effects of the inevitable explosion and fire after the simulated plane crashes were not considered in the design of the building. The point is; these buildings didn’t immediately collapse, they took almost an hour for Tower 2 and well over an hour for Tower 1 the North Tower to collapse. According to Ronald Hamburger a structural engineer investigating the disaster, "We have reason to believe that, without the fire, the buildings could have stood indefinitely and been repaired." The fire caused most of the life loss and building damage and the buildings were evidently deficient in fire protection.

All of the ‘plane caused’ collapse theories depend on the destruction of numbers of core columns by the plane crash impact and the subsequent failure of the remaining core columns by the heat of the fire. The core is the interior rectangular section of the building containing the stairways, elevators and bathrooms etc. An outer ring containing the large open office space surrounds the core. The outer ring, floor assembles consisted of long-span, open-web steel bar joists spanning the distance between the outer perimeter columns and the interior core columns. These bar joists supported a steel pan and concrete floor. Each façade had 59, high strength, steel box columns 40 inches on center. These exterior steel box columns were very strong and being 36 feet long, each was backed up by at least two of the 4-inch concrete floors on edge, built at 12-foot intervals vertically. Each box column was bolted to the column above and below and welded to spandrel girders ringing the perimeter at each story. The shiny aluminum skin covering each column would, of course be stripped by the planes and melted away by any fuel fire.

I have not as yet seen the enhanced videos but, I maintain that since, in the pictures I have seen, we can not really see the remaining columns because of the heavy black smoke issuing from the impact area; we cannot tell how many, if any, were severed. Using CAD simulations Tony Fitzpatric of Arup America determined that it took a direct hit by the engine’s shaft at 200 mph to punch through one steel H column and box columns are stronger than H columns and the interior core columns were stronger than the exterior perimeter columns. The planes would have been shredded passing through the perimeter columns, possibly taking out a few, and the number of interior core columns destroyed would have been much less.

I believe the intensity of the fire (as it relates to building collapse) was comparable to a heavy ordinary combustible fire after the explosion dissipated much of the jet fuel. According to Francis Brannigan author of Building Construction for the Fire Service, "…temperatures in excess of 2000 degrees are the rule in severe fires. The average person has no idea of the temperatures which can be reached in a quite ordinary fire."(Brannigan 1971, p245). The heat output of an interior fire is limited, by the amount of air reaching the combustibles and the smoke produced. In the standard furnace tests used to determine the collapse-resistance of building components, authorities switched from oil fires to natural gas since; "The smoke emitted by the fire at times seriously interferes with the transfer of heat by radiant energy within the fire building. Test fires use smokeless natural gas, so radiant heat transfer is important in tests."(Brannigan p206). A jet fuel fire would produce great quantities of smoke, which would reduce the radiant heat energy entering structural components. According to G. Charles Clifton HERA structural engineer, speaking of the fires in the Towers; "In my opinion, based on available evidence, there appears no indication that the fires were as severe as a fully developed multi-story fire in an initially undamaged building would typically be."(Elaboration..., p5) My point is that given the inadequate partial sprinkler system, deficient ‘fireproofing’ on the steel, the use of lightweight long-span steel bar joists, and large open areas undivided by fire walls, any uncontrolled large area fire would have eventually produced the same total collapse. The importance of early fire control, in most ordinary constructed buildings, to save lives by prevention of collapse in generally not appreciated even by engineers. It has not been that important, until now, in fire resistive buildings.

Instead of the columns failing first, I believe the weakest link was the long-span, open web, steel bar joists. The position of these joists, over the fire and the small-diameter steel elements of these joists would allow them to heat up to the failure temperature, (approximately 1100 degrees F.), much more rapidly than the massive columns which would act as a heat sink and conduct some heat away.

According to Deputy Chief, (Ret.) Vincent Dunn, FDNY writing in his book Collapse of Burning Buildings, "A large steel I-beam can absorb heat and take a relatively long time to reach its failure temperature, while a lightweight steel beam, such as an open web bar joist, can be heated to its failure temperature much faster." (Dunn, 1988, p142)

It has been shown that, at times, at the WTC, the fire resistance of both bar joists and columns were deficient, due to flaking off of sprayed on coverings in certain places. (NY Times, Science Sec. Dec 13, 2001). Removal of a small area of protective insulation from a bar joist would seem more detrimental than removal of a small area from a large column, since temperature would build up faster in the small element. According to Francis Brannigan, "the failure of any one element of the truss can cause the failure of the entire truss." A bar joist is a truss, and the failure of one bar joist can lead to successive failure of adjacent joists due to load transfer.

"In fact, successive failure of trusses appears to be the rule rather than the exception." (Brannigan p46). . As in a truss, a fire resistive building without built in redundancy depends on all the critical elements and their connections retaining their fire resistance and thus their integrity during a fire. The WTC exterior box column walls were shear-walls transmitting lateral loads through the floors to each other and to the ground. These exterior walls "together with the floors, formed a torsionally rigid framed tube fixed to the foundations."(Clifton p3). Removal of the floor rigidity by the heat caused sagging, break up of the concrete or collapse of these bar-joist floors removed much of the buildings horizontal bracing. Any and every critical element and its fire protection may be important in maintaining the integrity of the entire building at a serious fire. Since this situation is compounded as a building’s height and weight is increased, redundancy and extra protection should be increased through out a building as the height and areas are increased.

I surmise that as those floor sections, which were intact after the crash and fuel explosion, were weakened by the heat and let down their concrete loads and live loads onto the floors below, a progressive mechanical collapse began in the floors. In conventional fire resistive construction the spans are shorter and beams and columns rigidly restrained vertically, horizontally and diagonally, by strong connections and masonry walls built between columns. A progressive collapse due to impact loads is less likely since the masonry walls and strong connections between columns and girders can redistribute the loads. A floor collapse in a conventional steel-framed building would have been localized since the area between girders would be small. On the other hand "when huge spans are achieved by…trusses or space frames, collapse can be sudden, general and tragic." (Brannigan p215).

A pancake, V- shaped collapse or a lean-to collapse of a long span bar joist floor would impart a concentrated impact load on the floor below. I doubt weather the long span bar joists in the floor below could sustain such an impact, as well as steel I beams and reinforced concrete floors could. The connections of the joist ends to the columns, at the WTC, seem a likely spot for impact load failure. An impact causing a depression anywhere in the top chord of a truss could also cause collapse of the truss since such top chord is in compression and could buckle. The floors were providing lateral support to the exterior columns and core columns and in effect were integral to the stability of the whole structure. Removal of lateral support for enough of these columns, (by floor collapse) would allow the weight of the building above to buckle both the outer perimeter and interior core columns, letting down the entire upper portion of the building.

More likely, as the architect Mr. Malott points out in "Why the World Trade Center Collapsed", Nov./Dec issue of Designer Builder magazine, the bar joists themselves pulling with them the exterior walls" and the core columns started the collapse. "Steel members which sag due to fire will try to carry their loads as suspension members. This causes large horizontal forces; if they are transmitted to the fire wall, it can be destroyed."(Brannigan p253) It seems likely that such floor sagging in the Southeast corner of Tower 2 affected the corner core columns and/or corner perimeter columns causing the initial list to the Southeast just before the rapid, avalanche collapse of the 110 story structure.

The "bulging ripple going down the outside of the skin in advance of the collapsing floors" (Malott p12) in Tower 1 would have, in fact, been caused by floors collapsing ahead of the column failure. If it was a flat pancake collapse of the floors, the increasing dynamic weight of the concrete laden floors along with their live loads, hitting each level could easily break the connections to the columns or spandrels on each floor. The tips of the joist ends sliding down the interior face of the columns could have caused the "bulging ripple"; or this moving bulge could have been caused by the air pressure from the bellows effect as the collapsing floors compressed the air which pushed on and bowed out the windows and the aluminum skin.

In Tower 1 it appears the top floor or floors began failing first possibly because the top floors were receiving most of the super heated gasses rising up the damaged elevator shafts and other vertical openings. These fire gasses could have accumulated and heated the entire upper ceiling area of one floor, initiating a rapid sequential collapse of the joists. Or, more likely, after filling the upper floors (mushrooming) these heated gasses could have exploded, as happens at times in unventilated void spaces at serious fires, to start the initial pancake floor collapse. A third possibility as to the initial trigger for the Tower 1 collapse is sprinkler system water overloading one floor. For instance if the restaurant on the 107th floor were sprinklered and the heated smoke set off some or all of the heads, after a time, the water buildup over a large floor area could initiate the sequential bar-joist failure. "From the video footage this collapse appeared to occur (begin) uniformly around the building ("at or near the top of the building") and spread rapidly down to the floor above the impact region. That region than pancaked…" (Clifton, p8).

This type of flat floor collapse reminds me of bathroom floor failures in old six story apartment buildings. These localized, progressive collapses were so common, in the Bronx that we would try to stay out of bathrooms during apartment fires. One firefighter reported riding down such a bathroom floor collapse and said it felt like being in an elevator which momentarily stopped at each floor, as each bathroom floor hit the one below and broke the joists. Amazingly he stepped out unhurt at the ground floor. The reason for these failures was the weight of the heavy fixtures, mortar bed and tile floors, and fire attacking the dry rot in the wood joist ends. This wood rot was caused by constant water spills wetting the joists. (For more details on this type of collapse see Dunn p86).

The fact that the collapse began, apparently simultaneously, around the entire upper floor outer ring and possibly the inner core of Tower 1 rather suggests an explosion or rapid combustion of gasses such as carbon monoxide or other flammable vapor residue from the jet fuel, over-pressuring the area. "A room or area requires only 25 percent of its space to contain the explosive mixture for the entire area to explode."(Dunn, WNYF p9) This may have been another reason the fire temperatures in general not being any greater than an average fire- incomplete combustion due to lack of oxygen in the main body of fire. "The observed fire behavior points to temperatures in the building not being particularly severe — say no more than about 600 to 700 Deg. C. Possible reasons for this may involve the coating of combustible material in dust from pulverized concrete and wall linings (gypsum) and the volatility of the aviation fuel leading to large amounts of fuel being pyrolised but not burnt in the interior of the building."(Clifton, "Elaboration…" p6). Pyrolysis involves thermal degradation in the absence of oxygen. In a large area fire the high heat is distilling off more flammable gasses from combustibles than can be burned, since the available air is being quickly used up in combustion. These flammable vapors and gasses, produced by heat but unburned, can migrate to remote spaces due to rising convection currents, where if they attain the right mixture with air and are hot enough, will explode. This is one of the reasons fire-buildings are ventilated form upper areas by the Fire Dept. The overpressure produced by rapid combustion can vary from low pressure as in a flashover to severe as in a backdraft. The overpressure in Tower 1’s upper floors may have been strong enough to start the collapse but not strong enough to be noticed on the outside of the building. If you carefully watch the film of the collapse you can notice a sudden small loom up of black smoke from the top floor areas on the left and possibly right sides just before the avalanche collapse began.

Lightweight trusses are affected sooner by fire than heavy beams and since they can span such large distances, any failure becomes more serious than a short span element. Trusses were commonly used in supermarkets to eliminate columns and provide unobstructed views, so that people could easily see the food items. For a post fire analysis of a supermarket truss roof collapse, that killed six firefighters in 1978, see Ch.20 of Chief Dunn’s book. Until now the fire service has had little experience with ‘fire resistive’ floor truss construction, but its experience with common exposed roof trusses has been disastrous. According to Chief Dunn, "Truss construction is the most dangerous roof system that a firefighter will encounter." "A [unprotected] steel bar joist system may collapse after only ten minutes of exposure to fire."(Dunn p125).

The size of a fire is also a major factor that affects steel failure. "A large area fire in which flames involve much of the steel beam in a short period of time will heat the steel beam to its critical temperature more quickly. A so called "flash fire," suddenly involving a large area with flame, can heat steel rapidly to its failure temperature."(Dunn p142). Because truss construction is often used to provide this wide-open space within buildings another hazard is produced compounding the problem.

Large open areas, containing combustibles, within buildings, are a nightmare for firefighters because of the possibility of spread of fire, throughout the space and the resultant large volume of fire. This situation is exacerbated when elevators and standpipes must be used by responding firefighters, delaying the operation of hose streams and rescue. The difficulty in extinguishing such large, open area fires when extend throughout an interior space, arises because, as the fire in one section is extinguished and the hose streams are repositioned to attack another area, the fire re-ignites in the previous section by convected and radiated heat from the freely burning section. This hazardous situation occurs even in well-ventilated areas and fire-suppression in such large open spaces, within buildings, often requires the cooling of all areas at once, an effect, which sometimes can only be accomplished by sprinkler systems. According to Chief Dunn "The best kept secret in America’s fire service is that firefighters cannot extinguish a fire in a 20- or 30-thousand-square-foot open floor area in a high rise building." (From an excellent article on the operational problems related to design and construction, at high rise fires; see Chief Vincent Dunn’s article in Fire Engineering magazine December ‘95).

According to Chief Dunn, "The only real fire protection for a commercial or residential high-rise building is an automatic sprinkler and smoke-removal system to vent the smoke after the sprinkler extinguishes the fire." Mr. Brannigan comes to the same "…inescapable conclusion that full automatic sprinkler protection is vital to the safety of occupants of high-rise structures."(Brannigan p370) In my opinion, total sprinkler protection, if it had been installed and remained intact, would have provided enough cooling of the protected steel to at least slow down total collapse at the WTC. It certainly would have reduced the smoke and heat output to a more manageable level thereby saving many more lives.

Full automatic sprinkler protection means every area and room on every floor is covered by the discharge pattern of a sprinkler head. While a partial water spray system is often recommended and necessary for certain special hazard areas, it is not generally known that partial water spray systems can sometimes cause difficult problems if they are only installed in hallways or exit-ways, or only on certain floors.

If a fire starts in an unsprinklered area the fire may rage out of control in this area and the superheated gasses can flow across the ceiling to a sprinklered exit-way setting off the spray heads in this area. These sprinkler heads cannot control the fire since they are not over the fire, but will create expanding quantities of steam, at times, making line advancement down a hall or exit-way difficult or may even trap people if the exit-hall becomes untenable. Full coverage with a sprinkler system will solve the problem.

I found this out the hard way at a training exercise I was giving at the Nassau County Fire Academy. Several firemen were scalded by boiling hot water created by sprinkler heads, which opened in the hall well behind the nozzle as we advanced a hose line into the fire training room. A quantity of heated fire gasses rolled across the ceiling over our heads and set off the spray heads behind us producing this boiling cloud of steam and smoke. While this occurrence cools the ceiling gasses from superheated levels; as the water spray is converted into steam in expanding 1600 times, the process will turbulently redistribute these reduced but still scalding temperature gasses and water droplets from the ceiling level, pushing them to lower levels. Spray heads were not installed in the fire training rooms, of course, since we could not have had the training fires. We simply extinguished the fire and solved the problem, a solution that may not be that simple in a large area fire.

The other way partial sprinkler systems can be troublesome is if the fire in the unprotected area gets out of control and cannot be cooled quickly, the heated gasses can be forced up shafts or other openings to a remote floor above the fire and set off the heads there. Since the areas above an uncontrolled fire may be dangerous to enter the sprinkler water may not be able to be shut off in time, consequently accumulating on the floor or in the contents, overloading the floors, leading to collapse from overloading. Again full coverage by sprinklers will mitigate this problem by reducing or eliminating the production of these super heated gasses. On-off sprinkler heads and floor drains or scuppers to drain the water may also help. In spite of all these problems, "Sprinklers are the core of fire safety for the occupants of high-rise buildings" (Brannigan 1992, p502).

For some arcane legal reason the Port Authority of NY State and NJ did not have to comply with the New York City Building Code, and Fire Codes. If the Port Authority had to submit plans and get approval before starting construction and have been subject to inspection during construction by experienced Building inspectors and Fire inspectors and had to receive a certificate of occupancy before opening the building, many more lives could have been saved. All buildings built in the City should, at least, have to follow the City Codes, which also need some updating and revisions, but are still the most comprehensive in the world. The Port authority had a ‘policy’ to comply with City Codes, but still there were serious deficiencies in sprinkler protection, steel protection from heat, exit-ways & enclosures and building design, which would have been detrimental in any serious fires in these buildings. Sprinkler systems were not even built into the original buildings.

Long span, steel bar joists should be prohibited for floor construction in any new public building due to their early failure in fires.

I believe a survey and re-assessment of all existing high-rise buildings which use long-span, steel bar joists should be conducted in order to consider rebuilding them, using conventional methods.

I support Mr. Malott’s and Chief Dunn’s suggestions about encasing columns and beams in concrete or masonry for protection rather than using current ineffective spray-on fire retarding material.

Full-scale furnace tests for ‘long-span’, I beam floor assemblies with sprayed-on "fireproofing" should be conducted to determine their actual fire rating (endurance time), and what the effect of removal of sections of fire insulation would have on the collapse resistance of such ‘long span’ steel girders or beams.

Since long span floors are inherently weaker than short span floors, impact load tests to determine their progressive collapse potential would also be productive. Since it is impossible to evacuate a high-rise building rapidly, each floor in a high rise building should be able to support the impact weight of several floors collapsing from above; this in order to prevent a progressive collapse. Also the effect of an ordinary natural gas or smoke explosion on such long span floors should be determined. As building height and areas increase, columns girders and beams and walls and floors should be strengthened and redundancy increased accordingly with an increased factor of safety to take care of unexpected emergencies.

Evidently the crashing plane parts or the fuel air explosion destroyed some of the wall enclosures of the stairways and elevator shafts and cut off escape from above by filling the stairways with debris and heated toxic smoke. The elevators were also disabled due to shaft destruction and flaming jet fuel, pouring down the shafts. Tests should be developed to determine whether the impact load of a fuel air explosion alone or of a hose stream could affect the integrity of the "shaftwall" gypsum board, enclosing the stairways and elevator shafts. If an ordinary natural gas or smoke explosion, or the impact of an interior or exterior hose stream could affect the integrity of stairways or elevator shafts than then this type of "shaftwall"gypsum board construction should not be allowed for such use in any public building. As building heights increase more effective enclosures such as reinforced concrete should be required throughout.

The plane impacts apparently moved the buildings several feet wracking the walls thereby binding some exit doors in their frames. This suggests inadequate diagonal bracing throughout the buildings.

The ‘shaftwall’ and other drywall gypsum were dislodged in numerous places by the impact. This suggests the means of attachment was possibly inadequate.

Scissor stairs should be re-evaluated because of the possibility of both stairways being affected by a disruption of the enclosure.

Egress pathways leading between stairways or to the outside should be hardened to preserve their integrity.

Automatic fail safe door latches should be installed throughout the stairways to unlock all exit-way doors in the event of fire. This was to have been accomplished after the first bomb exploded in the WTC cellar in 1993. This suggests inadequate enforcement. Compliance with recommendations should be determined by actual re-inspections and not by reliance on written documentation.

Since elevators frequently fail to provide adequate Fire Department response to the floors of high-rise buildings, provisions for fire and smoke resistive, impact protected, elevator shaft enclosures should be developed for Fire Dept. access to upper floors and handicapped rescue from upper floors. Fire proof, ventilated vestibules as presently used in the old ‘fire tower’ stairways could be used. Ventilated ‘areas of refuge’ as elevator landing areas on each floor, could be used in conjunction with fire rated elevator shaft doors. If they can ring the entire, 16-acre, foundation area with 3-foot thick reinforced concrete 7 stories high to keep the Hudson River out, they can ring the areas of stairs, elevators and lobbies on each floor with fire walls and ventilation gaps to keep fire and smoke out.

Full sprinkler protection should be mandatory in all buildings over 6 stories or 75 feet in height, no matter what the building occupancy. We cannot always control the amount and type of combustibles entering the buildings.

Since hose stream coverage is limited and sprinklers are sometimes inactivated open area spaces should be limited to 2500 sq. ft. between fire containment walls and automatic fire doors.

Chief Dunn’s recommendation that air conditioning systems should cover only one or two floors should be implemented. Air conditioning systems should be designed to be able to safely exhaust fire gases directly to the outside after sprinkler extinguishment. Supply fans feeding fire area should be shut down.

I am sure there will be many additional recommendations for Building Code improvements, which will be gleaned, from the WTC catastrophe. The New York City Building code has, of necessity, evolved out of the many historic NYC disasters. We are naturally loath to imagine possible hazardous situations and disasters that can happen; and unless we actually experience them we apparently have difficulty developing preventative or precautionary measures. Effective regulations have been and are obtained from analysis of actually experienced disasters and through well-conducted experimental tests. History has proven that a good Fire Prevention and Building Codes, knowledgeable people and strong enforcement capabilities are absolutely necessary to build and maintain safe buildings. Critical code sections should be protected from special interest

changes. Code changes allowing smoke detectors to substitute for full sprinkler coverage in high rise buildings is a good example. The actual fire is the ultimate test of construction practices and the World Trade Center Towers failed the test twice.

Brannigan, Francis L., Building Construction for the Fire Service first edition 1971, second edition 1982 & third edition 1992, National Fire Protection Association — Batterymarch Park, Quincy, Massachusetts,

Clifton, G. Charles, "Collapse of the World Trade Center Towers" HERA structural engineer, HERA, Manukau City, New Zealand, http://www.hera.org.NZ/PDF Filer/World Trade Center. PDF

Clifton, G. Charles, "Elaboration on Aspects of the Postulated Collapse of the World Trade Center Towers" 13Dec. 2001, Collapse of the World Trade Center Towers; HERA, Manukau City, New Zealand, PDF Files/ Elaboration on WTC Paper. PDF

Darton, Eric, Divided We Stand, A Biography of New York’s World Trade Center, Basic Books 1999.

Dunn, Vincent, Collapse of Burning Buildings, a guide to fireground safety, Fire Engineering Books and Videos, a Division of Penn Well Publishing Company, 1988

Dunn, V, Why Can’t the Fire Service Extinguish Fires in High-rise Buildings, Fire Engineering Dec. 1995, Penn Well Corporation, 21-00 Route 208, South Fair Lawn, NJ, 07410-2602

Dunn, V, Backdraft (Smoke) Explosions, "With New York Firefighters" WNYF 3rd issue 2000, FDNY, 9 Metro Tech Center Brooklyn, New York, 11201

Fitzpatric, Tony, of Arup America San Francisco in "Simulating Airplane Attacks" by Nadine M. Post. Enr.com 12/10/01

Hamburger, Ronald. In "Structural engineer describes collapse of the World Trade Center towers" by Mark Shwartz -Stanford Report, Dec3, 2001

World Trade Center Locked Stairwells/ Evacuation Problems Accumulating Problems On… © 2001 Mike Barkly, http://www.mjbarkl.com/locked.htm

Fire Engineering Call to Action
From "Fire Engineering" magazine, http://fe.pennwellnet.com

WTC "INVESTIGATION"?: A CALL TO ACTION

Never again! In the wake of the World Trade Center, we are left with many thoughts-thoughts of friends lost, thoughts of devastated families, thoughts of the tremendous impact on so many lives for so many years to come. Yet, we-America's fire service-are left with one critical thought: How can we prevent a disaster like this from ever happening again?

Yes, it was the terrorist pilots who slammed two jetliners into the Twin Towers. It was the ensuing fire, however, that brought the towers down. Make no mistake about it: This high-rise collapse was no "fluke." The temperatures experienced and heat release rates achieved at the World Trade Center could be seen in future high-rise fires.

There are many, many questions to be asked by us about the World Trade Center collapse and its implications on high-rise firefighting across the nation. Some questions are political, many are technical, others are philosophical. Here are a few (in no particular order) to think about.

* Given the typical resources of most fire departments, can we be expected to handle every high-rise fire thrown at us? When was the last time your city manager asked you for a complete list of resources that you need to fight a high-rise fire, including personnel? When was the last time a high-rise building owner asked if you would like him to install a special "firefighter elevator" for your exclusive use during a high-rise fire? When was the last time a building code committee called up a "downtown" battalion chief and asked him what he thought of the unlimited area and height provisions found in all of the model building codes-is it OK if we allow a 400-story building in your battalion, Chief? The bottom line is, Can we really handle high-rise fires adequately? Who are we kidding? Isn't this the "big secret" that Chief Vincent Dunn has been talking about for years?

• Beware the truss! Frank Brannigan has been admonishing us for years about this topic. It has been reported that the World Trade Center floors were supported by lightweight steel trusses, some in excess of 50 feet long. Need we say more?

• Modern sprayed-on steel "fireproofing" did not perform well at the World Trade Center. Haven't we always been leery about these materials? Why do many firefighters say that they would rather fight a high-rise fire in an old building than in a modern one?

Isn't it because of the level of fire resistance provided? How much confidence do we have in the ASTM E-119 fire resistance test, whose test criteria were developed in the 1920s? ASTM E-119 is an antiquated test whose criteria for fire resistance do not replicate today's fires.

• The defend-in-place strategy was the wrong strategy at the World Trade Center. Many of those who ignored the directions to "stay where you are" are alive today because they self-evacuated. Do you stil l use defend-in-place strategies for large high-rise fires? When should you use them, and when should you not?

• We can see live broadcasts from Afghanistan, but we can't communicate via radios in many high-rise buildings. What gives?

There are many more questions, more than we have answers for. What is clear is that things must change. Where do we begin? By putting things in perspective. The World Trade Center disaster was

• The largest loss of firefighters ever at one incident.

• The second largest loss of life on American soil.

• The first total collapse of a high-rise during a fire in United States history.

• The largest structural collapse in recorded history.

Now, with that understanding, you would think we would have the largest fire investigation in world history. You would be wrong. Instead, we have a series of unconnected and uncoordinated superficial inquiries. No comprehensive "Presidential Blue Ribbon Commission." No top-notch National Transportation Safety Board-like response. Ironically, we will probably gain more detailed information about the destruction of the planes than we will about the destruction of the towers. We are literally treating the steel removed from the site like garbage, not like crucial fire scene evidence.

The World Trade Center disaster demands the most comprehensive detailed investigation possible. No event in our entire fire service history has ever come close to the magnitude of this incident.

We, the undersigned, call on FEMA to immediately impanel a "World Trade Center Disaster Review Panel" to coordinate a complete review of all aspects of the World Trade Center incident.

The panel should be charged with creating a comprehensive report that examines a variety of topics including determining exactly how and why the towers collapsed, critiquing the building evacuation procedures and the means of egress, assessing the buildings' fire protection features (steel "fireproofing," fire protection systems, etc.), and reviewing the valiant firefighting procedures employed. In addition, the Panel should be charged with preparing a detailed set of recommendations, including the critical changes necessary to our building codes.

Please e-mail this call to action to:

President George W. Bush (president@whitehouse.gov)

Senator Charles Schumer (senator@shumer.senate.gov)

Senator Hillary Clinton (senator@Clinton.senate.gov)

FEMA Director Joe M. Allbaugh (joe.allbaugh@fema.gov)

and to your own congressional representatives.

To obtain e-mail addresses for your representatives, go to www.senate.gov/contacting/index.cfm and www.house.gov/writerep/.

Disaster Foreshadowed:

Deputy warned of high-rise fires in 1995 article

By Graham Rayman

Newsday.com., October 31, 2001

In a high-rise building fire, elevators stall or shut down. Fire radios don't function above a certain floor. Fire ladders are too short. Civilians jump to their deaths. Air-conditioning ducts allow the fire to spread.

In short, it is extremely difficult to fight a major high-rise fire, particularly one on the upper floors.

These conclusions aren't from a report issued since the attack on the World Trade Center. Rather, they were written six years ago by Vincent Dunn, a deputy chief in the New York Fire Department. The 1995 article on high-rise fires in general, which appeared in Fire Engineering magazine, illustrated many of the problems confronted by firefighters six years later on Sept. 11.

Dunn, a nationally respected expert on high-rise fires who retired recently after 42 years, also included a warning.

"After fighting high-rise fires in midtown Manhattan, New York City, for the past 10 years, it is my opinion that the fire service has been lucky," he wrote. "Despite the limitations in fighting high-rise fires, we have not had a great loss of life or another multifloor high-rise fire."

In an interview yesterday, Dunn of Queens said there is nothing wrong with Fire Department tactics in high-rise fires, but he believes firefighter communications in such buildings can be improved and manpower can be added to units in high-rise districts. He also said a lighter weight oxygen mask needs to be developed.

"High-rise fires are the biggest challenge in the fire service," he said.

As for buildings, Dunn said elevators need to be more reliable, and interior antennas should be added to improve radio transmissions.

"The building owners have to prove to their occupants that their buildings are safe," Dunn said yesterday. "No fire safety director is going to be too influential. We have to get the confidence of the people back."

Since Sept. 11, fire department officials have said they are re-examining how to fight high-rise fires. The collapses of the Twin Towers have also generated debates in recent weeks over whether to rebuild the enormous structures and how to apply lessons of Sept. 11 in new construction.

John Jay College professor Glenn Corbett, of the Division of Fire Science, has called for a blue ribbon panel to examine the events of Sept. 11 for future lessons. "What's needed is an over-arching commission to coordinate all those activities and see where the gaps are," said Corbett, the technical editor at Fire Engineering magazine.

According to Dunn's 1995 article, high-rise buildings contain many barriers to effectively fighting a large-scale fire.

A major problem, Dunn said, is the time it takes to reach the floors containing the fire. "The long reflex time - the duration of time from receipt of the alarm until the first hose team discharges water on the fire - in a high-rise building allows the flames to spread beyond firefighters' control," he wrote.

Because the buildings are too tall for ladders, firefighters are prevented from fighting the fire from the outside or making exterior rescues, he stated.

Civilians jump, as happened Sept. 11.

"People trapped in a burning high-rise building who cannot be reached by your highest ladder will leap to their deaths, attempt to climb down knotted bedsheets and fall, scribble notes telling where they are trapped and drop them from smoky windows, or have their last cries for help recorded on fire dispatchers' telephones," Dunn wrote in 1995.

Among some of Dunn's other findings in his article:

The structural steel of a high-rise interferes with fire radio communication. Dunn cited tests conducted in the World Trade Center and the 102-story Empire State Building, which showed radios could transmit only to the 65th floor.

The large, open floor areas of high-rises allow fires to spread faster. "The best-kept secret in America's fire service is that firefighters cannot extinguish a fire in a 20- or 30-thousand-square-foot open floor area in a high-rise building," Dunn wrote.

Elevators often shut down, stall or malfunction, due to heat, flooding or structural failure. He cited an eight-year study, which found that the elevators failed at 59 of 179 major fires.

Central air-conditioning systems and elevator shafts provide tubes for the fire to spread through the building. "Ducts, shafts and poke-through holes penetrate fire-resistive floors, walls and ceilings."

According to Dunn, the standard strategy in fighting a high-rise fire, known as "defend in place," isn't effective. He defines the strategy as fighting the fire while the building occupants remain stationary.

Civilians, he said, will not remain at their desks. He cited the 1993 World Trade Center bombing, in which the occupants evacuated on their own after the building communication system was damaged.

"One of the lessons learned at this fire, as stated in the chief of department's postfire analysis, was that the 'defend-in-place' strategy does not exist," Dunn wrote.

Many of the problems firefighters faced Sept. 11 at the World Trade Center were foreshadowed in a 1995 article on the challenges of high-rise fires by retired FDNY Deputy Chief Vincent Dunn.

RESTRICTED ACCESS

Because the buildings are too tall for the use of ladders, firefighters are prevented from fighting the fire from the outside or making exterior rescues.

TRAPPED VICTIMS

Civilians isolated on burning floors will jump . At the Trade Center, even helicopter rescues from the roof proved to be impossible.

COMMUNICATION BREAKDOWN

Tests showed radios could transmit only as high as the 65th floor .When the Twin Towers collapses, equipment designed to strengthen radio signals was crushed along with the vehicles it was transported on.

ELEVATOR ISSUES

Elevators often shut down, stall or malfunction, due to heat, flooding or structural failure. On Sept. 11, survivors reported that elevators were stuck throughout the towers.

SPREADING FLAMES

Central air-conditioning systems and elevator shafts provide routes for flames to spread. After the planes slammed into the towers, flaming jet fuel cascaded down the shafts and scorched the lobby.

This article originally appeared at:

http://www.newsday.com/news/printedition/ny-nyhigh312440024oct31.story

The Towers: The Seen and the Obscene

By Meg Feeley

A friend of mine comes by Joel’s office at 315 Broadway, just south of Worth Street and above City Hall. It’s dinnertime. I’ve been working there, all afternoon.

"Want to see Ground Zero?" he asks, an expectant smile on his face.

Before I can even think about it, I blurt out, "No," and then wonder why I’ve declined, before the invitation even crosses the placenta of my brain.

This is the first time I’ve been south of Canal Street since early fall. I’ve been hiding out uptown, where I live, closing my windows tightly whenever the wind changes to blow northwards. A few weeks before, I had gone to hear a show at the Jazz Gallery, on Hudson and Spring, and felt my throat rasping after barely two hours. I retreated, quickly, to Harlem, eight miles from the site.

I’ve just spent the day working at the New York Environmental Law and Justice Project, writing a speech about the toxic air quality from the World Trade Center. I guess the metaphor hasn’t quite left me yet. I really have no desire to get any closer — I can imagine it, plenty. But the look on my friend’s face — he’s gone to all the trouble of walking over to the South Street Seaport for the free tickets — stops me.

"Sure," I correct myself. Both of my answers surprise me.

He softens and says, "Only if you can handle it."

We both know it isn’t the grim emotional clearing that concerns me, the sense memory that’s sure to accompany a mass grave. It’s the air I’m worried about. According to the New York Times, five months after the crashes, the air in the City is still twice as loaded with smoke and particulate as the surrounding suburbs thirty miles away. The information isn’t a headline. It isn’t even an article. Indicative of how ameliorated we’ve become to the compromised air quality in New York, it’s just a tiny statistic included in the national weather map the Times publishes every day.

We walk down lower Broadway, towards Fulton Street, perhaps eight blocks away. It’s five p.m., just after sundown on a crisp winter night. The narrow sidewalks are cluttered with office workers headed toward subways, and I forget where I am, forget what is only one block away. I think about other Decembers and Januarys, pretzel smells and shopping street vendors, all the times when I worked near here. Somehow, I forget where the Towers used to be, exactly. I never had to know, before, only to look up and see them, from anywhere around.

We come to a memorial, tee shirts and candles and notes and flowers pinned to a tall, wrought iron barricade and spilling onto the sidewalk below. Just past St. Paul’s Chapel, there’s a metal police barricade splitting the sidewalk in half. An orange-vested officer stands at the point of no return, from which we will have no choice but to walk up, then around, to the viewing platform, then back down to Broadway. The site is only a block away from what appears disarmingly familiar. My friend has his tickets out, but this time of night, after dark, there are no crowds, no tourists, and the cop waves us on without checking the slips of paper in his hand.

It feels vaguely ironic to gain access here without picture ID. This place has been a well-publicized armed camp, and moving freely feels dangerous. We walk up the plywood ramp, the stab of freshly-hewn pine snaps me out of this particular dream of commuter bustle, and then something else replaces it, shoving its way forward. The fine gristle smell on the wind starts the back of my throat up, itching.

The ramp to the viewing platform ascends, revealing the cemetery behind St. Paul’s Church. Joel took pictures of FBI agents in masks there, rooting through fine gray soot and office papers for evidence. While the agents aren’t identifiable in the photographs, they place Joel in Ground Zero when it was ‘hot’ — highly secret and off-limits to all but emergency workers and reporters. I told Joel to put those pictures away, but I love them, like an indelible memory of something that’s not there anymore. The fenced-in yard now looks odd and over-tidy, like it was brushed up from a four-hundred year-old bender, just for this occasion.

When we face the wreckage, my friend cries. I taste the grit on my tongue, and teeth. I watch him, and breathe in the deadness. Then I look out and see a white haze in the now-dark sky, obliterating everything else — sky, water, earth — from view, save the bright orange heavy equipment moving ceaselessly.

At first, the bright glow feels welcoming. It resembles the familiar bustle that Americans have come to know as progress: dirt being shifted, huge mechanical insects clawing through the night. But the halo of eerie white from the construction Klieg lights isn’t safe. It’s a symptom, like smoke and grit and the raspy sore throat, fluid sinuses, and tightened chests most New Yorkers suffered for weeks after the tragedy. This light is visible: at its’ source, its’ destination, and everywhere in between. As any good nightclub lighting guy can tell you, the only way to make light visible in its path is to diffuse it up, with fog, smoke, particulate, dirt.

It’s still there. Five months later, it’s still pretty bad down here.

I pull my scarf around my mouth and scrape at the film accumulating on my tongue with my teeth. I’ve waited what seems like forever to get this close, and now, I can’t wait to get out of here. But at least, now, I know what’s filling my nostrils and making me gag. It wasn’t like that at first.

In the days after September 11^th, public officials rushed to calm an uneasy public. Environmental Protection Agency Administrator Christine Todd Whitman arrived on site within days and her reassurances were widely publicized. She declared the air and water to be without contamination, even as monitoring equipment would prove to be clogged so badly with fiber and particulate that many test stations were rendered useless. A September 21 EPA press release states that "only" seven out of 97 testing sites showed asbestos levels in the air ‘above the level of concern’ and that New York’s drinking water was free of contamination from asbestos, bacterial contamination, pesticides and PCBs.

The push was on to restore normalcy, reopen the Stock Exchange and get people back to work and business. A New York City Department of Health press release advised residents returning to clean homes and offices that, "The best way to remove dust is to use a wet rag or mop. . . Where dust is thick, directly wet the dust with water, and remove it in layers with wet rags and mops."

The EPA’s testing, however, was flawed from the outset. Reports referred to levels of contaminants in the air, but never reported on the bulk asbestos levels in the vast amount of dust that was accumulating all over lower Manhattan, and in some cases, Brooklyn and New Jersey. The EPA neglected to report on fiberglass, suspected of being responsible for the persistent cough and sore throat of many a New Yorker.

At first, disclosure of this information, was extremely limited. The EPA posted only a small, selected portion of their data on their website. The New York State Department of Environmental Conservation denied an initial FOIL request from the Law Project for testing data, claiming that the information was relevant to an ‘on-going criminal investigation’. The information being provided, on the local and Federal levels, was largely palliative, substantively useless and in the case of the advice regarding removing asbestos-laden ‘dust’ with a dustpan, patently dangerous, in the face of what would turn out to be in the mix.

But mounting evidence of a toxicological nightmare began to emerge: The NY—based environmental reporting firm, Toxics Targeting Inc, generated a report on September 18^th on the World Trade Center. It listed 46 New York State reported toxic spills (both abated and not), 6 petroleum bulk storage sites (including one with 180,000 gallons of diesel fuel) and 21 registered hazardous waste generators and/or transporters located within 100 feet of the World Trade Center. All of this, presumably, became released into the environment in the inferno that smoldered for weeks, along a firing range containing hundreds of thousands of rounds of lead-based ammunition, and two power substations. As the fires raged below ground, a plume of smoke leached volatile organic compounds, including cancer-causing benzene, dioxins, PCBs and heavy metals, into the air.

We watched our surviving heroes — police, medical teams, firefighters, volunteer rescue, iron and steel workers, rush to the site in search of survivors. Most wore flimsy hardware-store masks, if anything at all, in the week immediately following the WTC collapse. The time elapsing from the events of September 11^th itself seemed echoed in the amount of protective clothing and gear worn by workers, increasing layer by layer, week by week, as did the clean-up procedures instituted before leaving the worksite. Now, the EPA has built an enormous tent onsite to provide workers with showers and changing facilities. The question is, why didn’t the City heed the cries of environmentalists and occupational health activists at the outset?

For all the laudatory press firefighters and police received for their heroism, it appeared that uniformed city employees were never comfortable that their health and safety was adequately protected in the aftermath. Many had developed doubts about the City’s Health Department, after being assigned escort duty for the trucks spraying pesticides in ’99 and ‘00, with no protective equipment and inadequate warnings.

New York’s Finest and Bravest weren’t reassured by the Mayor -- they were coughing their lungs out. They weren’t provided state-of-the-art respirators, which have cooling and hydrating mechanisms and thus encourage consistent use. They were bringing home asbestos and fiberglass dust on their clothes. The City was slow to institute spraying down the truckload after truckload of hot, dust-covered debris transported in open truck beds and barges along city streets, past schools, and on the waterways. And even as news reports began to filter down, the Mayor’s press office denied initial reports of danger, claiming that on-going monitoring showed no cause for long-term health concerns. Without proper abatement, full disclosure, and appropriate personal protective gear, workers and residents became exposed in the weeks after September 11^th to what would prove to be serious health risks.

And that’s how it was, that the Police Benevolent Association, perhaps one of the most close-knit unions in the country, called scruffy, lefty lawyer extraordinaire and super-hero of environmental activism, Joel Kupferman one day, asking for help. Many of us in the know thought that to be just a little bit odd — an indicator of the strange alliances that such times produce. Joel, who has personally comforted the family of at least one of the many persons of color shot by a member of the NYPD under questionable circumstances, who frequently spends his weekends as a National Lawyer’s Guild legal observer at demonstrations, and likes to say that he uses ‘commando’ tactics to win environmental victories, was just a little surprised.

But then again, cops were getting hurt. Detectives were out in Fresh Kills, combing the debris that arrived daily in nothing but their normal suits, their infamous shoes melting from the still-hot metals that piled up. Methane gas coming from the debris was enough to take at least two detectives to the hospital on stretchers.

And here’s where I can’t exactly be completely forthcoming. Suffice to say that Joel made his way into the then-iron-tight security that surrounded Ground Zero.

"Guess where I went yesterday," he phoned excitedly, and I couldn’t.

"Florida?" I stabbed, and he laughed. Joel’s mother, and my grandmother, live down there, and we both make frequent trips. When he said, "Ground Zero" it took a moment to sink in.

"How the heck did you get in? I asked, as if he had made it past yet another velvet rope in the naked city.

No one got in there. No one, except camouflage-suited National Guardsmen and City Dept. of Environmental Protection pickup trucks and FBI agents and reporters and uniformed services of all stripes, combing the streets, not half of them wearing masks. It was, at the time, an unimaginable city within a city.

Soon after the PBA rep sent over a copy of the report of injuries their membership were sustaining, the Law Project got a call from the Operating Engineers Union, saying they, too, were concerned.

And that’s how Joel, in a Tyvek protective suit, doubled socks, and a full double-cartridge respirator mask, managed to scoop samples of the thick gray film that was coating the area. He brought his partner to take photographs. They show block after block of stringy, friable asbestos, on cars, sidewalks, buildings, chain-link fences and the sides of telephone booths. Downtown Manhattan looked exactly like those awful pictures of the ceiling rafters in asbestos plants. It’s hard to understand how public health officials wouldn’t assume that rescue workers might suffer occupational-level risk of asbestosis and mesothelioma, known consequences of exposure to friable asbestos.

Justice, though, is sometimes disarmingly simple. Joel spooned samples from the backs of cars, the streets, and the sides of buildings into plastic bags marked with the date, time and location of collection. No one stopped him. The next day, he sent them to a local laboratory, ATC, frequently used by the Board of Education in testing schools for asbestos levels.

The reports come back within hours. Three of four samples contained between 10 and 15% fiberglass, an eye and lung irritant and, according to the National Toxicology Program, "reasonably anticipated" to cause cancer. (Because it is not a ‘known’ carcinogen, the EPA declined to report on levels.) One of the four samples showed more than double the percentage of asbestos (1%) at which a substance is legally designated as hazardous.

The results from additional samples sent to an independent Virginia laboratory, Environmental and Toxicology International, were even more disturbing, showing up to 5% chrysotile, friable asbestos in some samples (five times the legal threshold), and fiberglass ranging from undetectable to 95% of the dust sampled. Perhaps most chilling, some of the samples contained human bone fragments.

On September 28, 2001, Daily News reporter Juan Gonzales broke the story, "Health hazards in air worry Trade Center workers" with little more than this data. Other stories began to appear, questioning the Board of Education decision to re-open Stuyvesant High School blocks away from the site within weeks of the collapse. It is interesting to note that soon after the Daily News story appeared, the NYC lab, ATC, was directed not to do any additional testing of bulk dust samples for private individuals.

The EPA continued to issue press releases claiming that air monitoring, with the exception of a few stations directly at the site itself, showed levels of asbestos ‘below concern’.

Most of the press equivocated. On October 11^th, the NY Times reported that, ‘independent testing by a company hired by the New York Times . . . concluded that the outdoor street level air in the vicinity of the trade center does not contain poisons or toxic substances, especially lead and asbestos, in levels sufficient to cause long-term public health concerns." TV news on CBS and other stations took pains to offer ‘balanced’ reporting, countering allegations with EPA assurances.

They say politics makes for strange bedfellows. If there’s one thing the 2001 Mayoral election in New York proved, it’s that catastrophe can make for love matches that are downright absurd. It’s hard to imagine how or why officials charged with the protection of public health could minimize the potential adverse health risks of a terrorist attack. Perhaps both from a standpoint of litigation, as well as calming a fearful public, it seemed the easiest solution, at the time. There was an immediate flurry to compensate victims with charity funds and Federal dollars, but the potential for lawsuits was incalculable. Was it in the interest of officials, and perhaps Citibank, as well, with a major financial interest in the site to keep information from being fully disclosed? With a business relationship between the bank, and the husband of EPA Administrator Whitman, this has become the focus of an on-going Congressional inquiry.

Joel likes to say that his favorite ‘commando’ method is using Freedom of Information requests, but I say that Joel’s secret weapon is that he talks to people. Or, more accurately, he listens. The knapsack holding his laptop computer changes his yogic gait into one of a man with a ‘heavy load’ on his back. I suspect it makes him look and seem approachable, and so does his smile. Joel walks or takes the subway everywhere, a sheaf of dog-eared paper perpetually jammed under his arm. In the early days, he prepared a leaflet, "Downwind of Disaster" which made the case. The affable guy spent days walking around downtown, handing out his flyer to anyone who would stop.

Everywhere, he met people who doubted the reassurances they were hearing. On an elevator, he met an asthmatic health department worker who claimed, between puffs on her inhaler, that she was unable to use a mask on the job, after returning to work less than a mile from Ground Zero. He met tenants from surrounding buildings whose landlords provided either improper asbestos abatement, or no professional abatement whatsoever. It was those people that kept him going, in spite of living from small donation to small donation, depending on interns and volunteers and free-lance writers to contribute what we could.

Finally, in response to Joel’s FOIL request, the EPA turned over a case of paper, the air sampling results taken in the vicinity. With the help of Monona Rossol, an industrial hygienist, he sifted through the data, and it was not good news. The Daily News front page of October 26 screamed, "Toxic Zone: Levels of benzene, dioxin, PCBs and other dangerous chemicals at Ground Zero exceed federal standards." At last, the results of the EPA’s testing were posted on their website for all to see. This, finally, fulfilled a basic tenet of urban environmentalism that is so often compromised in the name of the public good: that of the right of communities to make decisions that affect their health, fully informed.

Today, the information we have on the substances that came from the Towers’ collapse is growing exponentially. The EPA’s Ombudsman’s office has launched an investigation into the actions and response of the agency around the World Trade Center. In response, it would seem, a suspicious move on the part of the administrator herself threatens the investigative autonomy of the office.

The St. Louis Dispatch, of February 9, 2002, reported that the U.S. Geological Survey had a "team testing the particulate dust covering the immediate area [of the World Trade Center. They] found that some of the dust was as caustic as liquid drain cleaner and alerted all government agencies involved in the emergency response." The article reports that USGS officials are unclear as to why the EPA didn’t release the information.

Medical testing of rescue workers has now begun in earnest, with some of the most prestigious occupational health facilities in the country on site. The preliminary results are frightening: fire fighters, police officers and abatement workers are presenting with onset of asthma, chronic cough and respiratory irritation, and even GERD (acid reflux) as a result of the exposures they suffered after the collapse. The true effects, on rescue workers, as well as residents and workers may not become known for decades.

What is certain is that the toxicity of the site is far in excess of what was first disclosed, and that it may well fall under the conditions for being declared a ‘Superfund’ site. This is what the NYEL&JP has demanded, in light of the level of toxicity present. It is yet another vision of what the Trade Towers have become.

All things, no matter their cold, statistical reality, are subject to a morphic and personalized existence. Everyone, these days, seems to have a different vision of what the Towers were, are, or should be; what they meant, what they were intended to be. The buildings were designed, in part, for their symbolic meaning. Certainly, they were destroyed for what they stood for. It is no longer what they measurably were -- height, width, depth -- for they’re gone now, erased from the scene-scape, forgotten one block away. Their legacy will morph and shift until we are comfortable. From office buildings and workspace into sarcophagi to vestibule for an out-sized national ego. Now, they can be whatever we want them to be, and the imagery has shifted again.

To my surprise, the viewing platform revealed a visual blank slate, a ruin razed clean. Somewhere, I remember reading that Americans detest their ruins, and get rid of them quickly. I know that we are digging to recover the bodies of the dead, and perhaps some gold in a vault. All that is good, but so too are we sweeping clean this valuable real estate, scrubbing away our pain, trying to erase that hour that changed us forever.

Weeks after I visit the site, friends of mine, visiting from Canada, want to see ‘Ground Zero’. I am reluctant to take them, for what is there, really, to see? If they have no memory of the place to start, what is there to miss? Besides, we don’t have tickets. We walk past, and I simply point from the Staten Island Ferry and say, "That’s where they used to be." They murmur a heavy assent. It is, simply, impossible to say what ‘they’ used to be.

These buildings, for everything else they were, were also land mines towering above the killing field —safe, so long as they remained undisturbed. After what I’ve seen, read, wrote and heard in the last five months, my vision of the complex has changed again. Like finally turning the package over to read the calorie count, I’ve seen reports and printouts and data that have destroyed the benign illusion of these buildings, revealing something much more insidious than even the disaster we watched en masse.

Now my vision of the Towers is of two huge upright milk containers, filled with inert toxic gasses and particulate. When the milk cartons went over, there weren’t enough paper towels in the world to clean it all up. What was in the World Trade Center wasn’t all that unusual, but rather the common substances found in most modern offices. With the astounding amount of office space housed within, the complex may have been the largest single collection of routine, normal, toxic materials from partitions to desks to computers to the glass in the windows, anywhere.

Asbestos, and other mineral-based fire retardant sprayed throughout the building on structural members, flooring, carpets, tiles, waxes, cleansers, upholstery, particle board, sheet rock — these were the materials that made the World Trade Center remarkably undistinguished. From the old fluorescent fixtures with PCB-laden ballasts in the sub-basement levels, to the minute amounts of mercury in the new fluorescent bulbs, to the storage of fuel and firearms, the amount of heavy metals present was substantial.

What was unusual, of course, is that on September 11^th, they were subjected to an ingenious attack, which beyond explosion itself, introduced jet fuel and impossibly hot temperatures to the structures. And by now, most of us are aware of the ‘hollow tube’ structure that made the buildings as susceptible as they were to this particular type of attack. What is significant about the WTC, and the months of plumes and fumes that burned, exposing residents and workers to health hazards which we are now just beginning to understand, is that every other office building in America is largely the same.

Had a similar attack been launched at Times Square, or the Sears Building, or downtown Minneapolis, for that matter, the effects would have been different, and might have been largely the same. It could have been worse, as difficult as that is to imagine. Every contemporary office building contains synthetic carpets and plastics that off-gas, exposing workers to poor indoor air-quality without a violent attack, an unseen and silent health risk that becomes potentially lethal in a fire. Most buildings built before 1970 are subject to the EPA’s policy of leaving non-friable asbestos insulation in place. This policy, while probably the safest thing to do at present, is literally a ticking bomb that our descendents will have to deal with, as buildings come down, even through planned demolitions.

Now that the austere marble lobbies and towering symbols of might have been reduced to a fine dust many of us found ourselves breathing, the Towers are truly a part of our collective body and consciousness. Now that we’ve seen the ruins we’ve always feared seeing, what we have wrought may be far more incisive than even our worst enemies might imagine.