And I will now summarize our work to date and our plans for the future. We announced this investigation saying it would be thorough, open, and result in meaningful recommendations.

It was thorough. NIST was able to acquire and test enough steel from the buildings to have confidence in our findings. We acquired more than 7,000 photos and 150 hours of videotape. We interviewed nearly 1,200 survivors and first responders, and we gained access to key information about the building's design and construction.

It was also open. We sought public comment on our plans even before we began the investigation. We held numerous briefings for the public, published reports on our progress, and solicited comments. We sought input from an advisory committee of outside experts. We established a special liaison with the families of victims, and communicated regularly with the relevant organizations in New York City. This was no academic exercise. We were charged with developing meaningful recommendations, and we have done that. Using the recommendations from this investigation to make improvements in the way people design, maintain, and use buildings has just begun. NIST is working vigorously with the relevant communities to turn the recommendations into action.

The direct link between the terrorist-initiated airplane attacks, the ensuing fires, and the collapse of the towers was established through extensive testing, analyses, and computer modeling. Here, you see a model of the aircraft as it enters Tower 1, and the damage that was inflicted as debris and jet fuel spread over multiple floors. These models helped us to estimate the internal damage to the structure and fireproofing that was not visible in photos and videos taken from the outside.

In WTC 1, the fires weakened the core columns and caused the floors on the south side of the building to sag. The floors pulled the heated south perimeter columns inward, reducing their capacity to support the building above. Their neighboring columns quickly became overloaded as columns on the south wall buckled. The top section of the building tilted to the south and began its descent. The time from aircraft impact to collapse initiation was largely determined by how long it took for the fires to weaken the building core and to reach the south side of the building and weaken the perimeter columns and floors.

NIST found no corroborating evidence for alternative hypotheses suggesting that the WTC towers were brought down by controlled demolition using explosives planted prior to September 11, 2001. NIST also did not find any evidence that missiles were fired at or hit the towers. Instead, photographs and videos from several angles clearly showed that the collapse initiated at the fire and impact floors and that the collapse progressed from the initiating floors downward, until the dust clouds obscured the view.

Group 1. Increased Structural Integrity

The standards for estimating the load effects of potential hazards (e.g., progressive collapse, wind) and the design of structural systems to mitigate the effects of those hazards should be improved to enhance structural integrity.

Recommendation 1. NIST recommends that: (1) progressive collapse be prevented in buildings through the development and nationwide adoption of consensus standards and code provisions, along with the tools and guidelines needed for their use in practice; and (2) a standard methodology be developed�"supported by analytical design tools and practical design guidance�"to reliably predict the potential for complex failures in structural systems subjected to multiple hazards.

My name is James Harris. I am President of a structural consulting firm in Denver, Colorado. I have long been involved in the development of standards for structural engineering practice here in the U.S. as well as internationally. I have chaired the ASCE/SEI committee that prepares the standard ASCE 7 Minimum Design Loads for Buildings and Other Structures for the last three editions. I am also a member of the American Concrete Institute Committee that prepares the standard for the design of building structures, and the American Institute of Steel Construction Committee that prepares the standard for the design of steel buildings.

ASCE/SEI commends NIST for their thorough study and for the thought-provoking findings and recommendations. We also commend the Congress for providing the funding for this worthwhile study. Even though the first lesson of September 11 is to direct resources to prevention of such attacks, we see important lessons from this tragedy for improving the performance of buildings in emergencies that are more ordinary than the attacks of September 11.

ASCE supports careful consideration of all of NIST's recommendations by the broad community that develops standards and building codes for this country. NIST's study built upon and extended the work of the Building Performance Study Team that ASCE formed and FEMA supported immediately after the tragedy, and which produced their report in 2002.

Some of the other recommendations will require considerable time to develop a knowledge base in the affected professions.

ASCE/SEI feels that some of the NIST recommendations need further clarification and discussion.

Our profession is responsible for protecting the public to the best of our abilities and to seek new technologies to help us meet that charge.

While not every NIST recommendation may be ready for enactment as is, ASCE/SEI is moving forward with discussion of the issues and their implications for structural engineering practice, and looks forward to working closely with NIST to clarify the application of these recommendations.

NIST Recommendations Referenced:

Recommendation 1. NIST recommends that: (1) progressive collapse should be prevented in buildings through the development and nationwide adoption of consensus standards and code provisions, along with the tools and guidelines needed for their use in practice; and (2) a standard methodology should be developed�"supported by analytical design tools and practical design guidance�"to reliably predict the potential for complex failures in structural systems subjected to multiple hazards.

Thank you, Chairman Boehlert. Chairman Boehlert and Members of the House Committee on Science, my name is Glenn Corbett. I want to thank you for the opportunity to testify again before you concerning NIST and the World Trade Center disaster investigation. Before I discuss the investigation, I would first like to extend my thanks to you, Chairman Boehlert, and the House Science Committee, for initiating the creation of the National Construction Safety Team Act, and shepherding it through Congress to final approval by President Bush. The American public is the beneficiary of this critical legislation, and will reap the benefits of your labors through the savings of lives and the construction of safer buildings.

Additionally, I must also note that although I am a Member of the Federal Advisory Committee to the National Construction Safety Team, I do not speak on their behalf. My testimony represents only my own opinions. I recommend that the House Committee on Science review the annual reports of the NCST Advisory Committee for details on their perspective.

Over three years have passed since NIST began its investigation into the World Trade Center disaster. We now have come to the conclusion of this $16 million effort of a search for answers about what happened in the twin towers. The investigation has taken much longer than anticipated, including the fact that the World Trade Center Building Number 7 investigation will likely not be completed until next summer.

Although NIST has done quite a bit of work and has amassed many thousands of pages of useful research, I feel that the investigation has fallen far short of what is needed. From the beginning, I had hoped for a true investigation with a tight set of specific recommendations at the conclusion, that could be immediately passed to our national code writing groups and trade associations. Instead of passing a blazing torch of detailed recommendations, this lengthy marathon race has resulted in NIST giving our model code writing groups only a handful of flickering embers that, although generally good in principle, are entirely too vague. The model code writing groups now have to wait even longer while NIST hires an outside organization to prepare a set of recommendations that actually can be assimilated into our construction codes.

During the course of the WTC investigation, I have had serious concerns about some of the findings and conclusions that NIST has drawn. Other individuals, including some people on the Federal Advisory Committee, have also had concerns. While this hearing is not the appropriate place to debate technical issues, I would suggest that a more formal mechanism be developed to officially address comments from the public. Such a protocol should include the technical basis for which NIST rejects or accepts the content of a public comment.

Overall, I have been disappointed by the lack of aggressiveness that has characterized not only the World Trade Center investigation, but the Rhode Island Station Nightclub investigation as well. Instead of a gumshoe inquiry that has left no stone unturned, I believe the investigations were treated more like research projects, in which they waited for information to flow to them. In both investigations, they were reluctant to use the subpoena given to them under the NCST Act. To some extent, this lack of assertiveness was likely the result of legal opinions given to NIST by staff attorneys.

Recently, this situation was greatly amplified by NIST's reluctance to respond to Hurricanes Katrina and Rita under the banner of the NCST Act. I suggested to NIST that they assemble an NCST team for Katrina before it struck the Gulf Coast. They actually sent a handful of people a week after Katrina hit, and only recently sending a much larger group of researchers to the area. Curiously, they have decided not to respond under the NCST Act.

To their credit, NIST has brought many talented people to the WTC investigation. They have expended a tremendous amount of effort, compiled a great deal of technical data, pushed the technical limits of computer models, and identified the general areas of concern where improvements in safety regulation and practice are called for. They are to be commended for their extraordinary research efforts, given the immensity of the project.

Where do we go from here with regard to the World Trade Center? The ball is in NIST's court, and it is up to them, with their contractor, to quickly whittle the desirable but too general recommendations into well-defined code language that can be quickly moved through the model code review process. I strongly encourage them to be bold, use their best engineering judgment, and come up with clear and concise code language. High rise fire safety and safety in general is held in the balance.

When I look to the future of the NCST Act, sadly, I find it necessary to recommend that serious consideration be given to finding a new agency to implement the Act. I don't think that NIST is the right place for the NCST. Their nonaggressiveness, their absence of investigative instinct, and the palatable lack of interest they have shown in the Act has brought me to this conclusion. NIST is an organization of exceptional scientists and engineers, not detectives.

Short of creating an entirely new Construction Safety Team Board, I would recommend that serious consideration be given to moving the NCST to the U.S. Chemical Safety and Hazard Investigation Board. They are a close fit. They investigate explosions and chemical disasters in and around structures. They deal with many of the same code writing bodies that NIST deals with, including some of the organizations represented on this panel today. More importantly, they are solely an investigative agency that issues recommendations. Perhaps their purview could be expanded to include the NCST Act.

Some of them, like the one I happen to be the most concerned with, number one, increasing the structural integrity in buildings, and providing resistance to progressive collapse. That is not an easy nut to crack. In fact, there, we probably even need more basic knowledge. And so, it is going to take a long time before everything that NIST has uncovered and recommended is addressed, and it will not all happen in one fell swoop.

And after the NIST investigation began, we set up a High Rise Safety Advisory Committee to look at high rise safety, and to be ready for the NIST report, because we recognized that it is really society's role to take the recommendations, the science, and set the thresholds, and determine which buildings should these recommendations apply to, and to weigh that and balance the risk and the safety as it is.

Were we frustrated that the recommendations were not more specific? In some cases, yes, because the other investigation that we were familiar with was the Station Nightclub investigation, and that investigation done by NIST was much more specific than that World Trade Center investigation. So, we feel that they could have been more specific in some cases, but again, you know, just by its very nature, the investigation, the largest building failure investigation, I think, is going to come up with some science that needs to be studied and thought about, and all the viewpoints need to be brought in. And that is what we are doing.

Well, it is good to know that we are moving forward on several fronts, but we are impatient, understandably. A lot of people are impatient, understandably, and a lot of people want action as quickly as possible. And I am reminded of another issue, acid rain, which is one of my pet concerns, and people kept calling for more studies, more studies, more conversation, more give and take. And I remember Governor Kean, at the time, who ironically headed the 9/11 Commission, Governor Kean saying if all we do is continue to study the problem, we will end up with the best documented environmental disaster in history.

So, I think we are all very anxious to get going with some degree of specificity, with something that is tangible, that we can get a hold of, and we appreciate the fact that some of these things are going to be time-consuming, but time is a wasting.

we will end up with the best documented environmental disaster in history.

Dr. Jeffrey, I was struck by your testimony and by Ms. McNabb's about whether NIST recommendations for building codes should apply to every building, every commercial building the same. Most of the discussions about our terrorism risk have assumed that there is some possibility that there would be truly a random attack on any garden variety commercial building in America, but the most likely targets are what homeland security has called iconic buildings, buildings of high symbolic value. The World Trade Center. The Pentagon, obviously both of those. The John Hancock Center. The Empire State Building. Dr. Jeffrey, I have practiced law for a while, in a garden variety six story office building in the North Hills area of Raleigh called the Landmark Center. It was Class B space. That was fine. I had kind of a Class B law practice. Why on Earth would you expect the Landmark Center on Six Forks Road in Raleigh to have the same standards of preparation against terrorist attack that the John Hancock Center would have?

Thank you, Mr. Miller. Actually, the actual building codes that get adopted are at the State and local level. First, you know, that is part of the political process within the State and local governments as to what is appropriate for that specific setting.

Secondly, in the report, NIST does recommend that the owners of the iconic buildings, much like the ones you have mentioned, may want to view a higher level of preparedness than the average�"the report specifically does not try to recommend that every building in the Nation be able to survive an attack with a fully loaded 747. And so, it does try to make that distinction, and calls out the iconic buildings separately.

Should that be something dealt with by�"that sliver of commercial properties, that are the most likely terrorism targets, should those be dealt with by Congress, rather than leaving that to local building codes?

Mr. JEFFREY. I am not sure that I am actually qualified to respond to where the State and local versus federal roles should plan.

Mr. MILLER. All right. Well, Ms. McNabb, what is your thought on this? Do you think that the Landmark Center ought to have essentially the same standards applied to it that apply to the John Hancock Center?

Chairman BOEHLERT. Let me interrupt here. Now, I won't take this from your time, but you know, this is not just about terrorist attack. It is about wind, it is about fire, it is about a whole bunch of other things that may not involve any terrorist activity, but we know we don't know enough, and I am not quite certain we know what we don't know, but we know we don't know a hell of a lot, and with that, Dr. Jeffrey�"�"

Chairman BOEHLERT. Let me ask the other panel members. What do you think about that? I mean, should we have more information publicly available for review and examination and comment and response? Mr. Corbett.

Mr. CORBETT: Definitely. The answer is yes to that. That has been one of my concerns on the advisory committee, is that for example, all the information dealing with the first person accounts, the interviews that NIST had conducted, at one point, there was discussion about destroying that information. No decision had been made, but that was a possibility at one point, and I think now, NIST has basically said at this point, it won't be destroyed, but we are still not sure how it is going to be disclosed. And I think for the benefit of myself and other people that are, weren't part of the investigation, that we are kind of on the outside looking in. This is critical information for them for other research they are doing also. But also, to verify the conclusions, the findings, and of course, the recommendations that were, that come about. So, critically important to get that information, as much of it that can be given.

The more science that NIST can give us, and the more information that we have, I think the better off it will be for the public, because they will understand that building regulations don't just come out of a vacuum and from the building police, that there is a reason for, perhaps, raising the cost of construction, or perhaps making some trade-offs, or doing things differently.

Chairman BOEHLERT: In almost all cases, more information, rather than less, is desirable if you are reviewing and serious about making recommendations to prevent something in the future from happening.

Did you want to add something?

Mr. JEFFREY: Just a short statement, that we are absolutely committed to that. We agree with that. I think the entire process that we have tried to follow has been as open as possible, as described. The number of open meetings, the number of comments received. And we are committed to trying to release as much of the data as we legally can, and so, we know, we approve and agree with the statements.

You made, I think, a very potent point, which is that there was a sensitivity that the NIST study was not detailed enough, that it seemed to have some political ramifications. They may not have been on the ground, and many of us have been to Ground Zero. I serve on the Homeland Security Committee, as many of the Members of this Science Committee does, and we have a very visual sense of the need.

Can you share with us what more you would want, would have wanted NIST to do, or where were the political correctness issues that you think really didn't do the appropriate, or did not give the appropriate response?, particularly as you have faced a personal loss in the loss of your son, and you have my deepest sympathy?

Ms. REGENHARD. Thank you very much.

First of all, I just want to preface my comments with saying I often introduce myself in the way that I am basically just a little mother from the Bronx, and really, that is what I am, and I am not a technical person. However, I do have, over the last four years, you know, the input from my wonderful technical advisory panel, which represents some excellent, excellent people in the academic fields, and certainly, you know, in structural engineering, fire protection, architecture, and evacuation specialists.

So�"but to get back to your question, you know, political correctness. I have seen, and the other families of the victims have seen the aftermath of 9/11 to be somewhat definitely flavored by political correctness in many, many ways, in so many ways. But certainly, with the NIST investigation, I mean, I understand that it is a wonderful organization of scientists, and scientists are not trained to be like NYPD detectives. There is a professional and academic way that these kinds of organizations deal with one and with other entities. And you have other professional people in that investigation that should have been really interrogated, such as the Port Authority, such as their building plans. You know, the Port Authority never turned over their building plans until there was an article about it in the front page of the New York Times condemning them, or not condemning them, but accusing them of really not coming forward. That is one of the examples. People like the chief structural engineer for the first World Trade Center, you know, his work should have been investigated, because after all, he was responsible for the design of that building, and the subsequent, and yet, instead of that, he was sort of dealt with in a friendly basis, and he was actually put on the payroll to explain his plans and all that.

So, there were these very, you know, maybe because I am a layperson, I can't understand why these entities that should have been scrutinized and investigated were sort of taken in and became part of the investigation. You know, that is just one of the examples of where the families were really, really deeply concerned about that. And also, the avoidance of certain things that were not politically correct, like the avoidance of blaming anyone for anything. I mean, we all teach our children to obey the law, and to respect authority, and not to break any laws, but yet, when we have this investigation of the, I would say the needless deaths of nearly 3,000 people, no one is to be blamed. It is handled so gingerly. I mean, there is a reason why nearly 3,000 people are dead, and I feel the majority of them needlessly, but yet, the approach of these investigations is very, very tentative, and no one wants to put anyone on the line, and no one wants to look into what was the effect of the Port Authority immunities from building and fire codes?

If someone said to me what are the two major grievous examples of what went wrong on 9/11 in those buildings? I would say the two things are the Port Authority exemptions and immunities from New York City building and fire codes, and the wholesale failure of the FDNY radio communications, and the wholesale failure of the Emergency Management System of the City of New York and the Port Authority. And these are the crux of the matter. This is the bottom line. Yet, these are the issues that were, you know, skirted around and, you know, tiptoeing through the tulips, instead of�"and still, today, I have to fault both the 9/11 Commission and the NIST investigation for not taking a stand, for not saying that in our country, no building should be above the law, especially the Port Authority buildings that were the tallest and largest buildings in the world, that at that time, was built to contain the largest number of people in the world, and yet, those buildings were allowed to be exempt and immune from building and fire codes, essentially above the law, and now, we are allowing the Port Authority to do the same thing all over again.

The new World Trade Center and the memorial, and every single building down there on that property will be just as exempt and immune from every single New York City building and fire code as the first one. That is an abomination. That is a sin. That is an outrage against humanity. And you know, I am sorry to get emotional. I expected the NIST investigation and the 9/11 Commission to take a stand on that, but you know what, it is only the average Joe Q. Citizen. When we break the law, we have to pay the consequences, but when we have these huge organizations breaking the law, I feel they are not held to the same standard as an average citizen, and that hurts.

Chairman BOEHLERT.�"gentlelady's time has expired.

I would report that we anticipated, in developing the legislation that authorized the report and everything, we anticipated that there would be a reluctance on the part of some to provide information. There would be inertia. And that is why we gave subpoena power to NIST, to go in and get the information, and it was not NIST's role to assign blame. It is NIST's role to investigate, to determine what went wrong, to make recommendations on how to go forward, and that is what we are determined to work cooperatively with Dr. Jeffrey and the NIST people, to make certain it happens the way we want it to happen, and that we don't drag our feet, or we don't issue a report, and sort of say gee, we did a great job. We have this report, and have it not as specific as we would like, or there be a lack of follow through.

Mr. CORBETT. Yes, thank you. I commented on this during my testimony, and I still believe the NCST would have been useful down there, especially given the fact that the problems we have had with the World Trade Center investigation, you know, securing evidence, getting evidence early on. I mean, we were very heavily reliant on computer models to tell us what happened to the Twin Towers, because we lacked that physical evidence, because there wasn't an Act when the Trade Center was hit.

Q8. Dr. Jeffrey, some of Ms. Regenhard's and Dr. Corbett's criticisms of NIST's reluctance to use the full authority of the National Construction Safety Team (NCST) Act are echoed by the NCST Advisory Board. What is your response?

A8. NIST believes that it has used appropriately the authority of the National Construction Safety Team Act. NIST has obtained all available documents and evidence essential to carrying out a thorough and credible technical investigation. NIST believes the findings from its investigation are well justified on the basis of those documents and evidence.