National Construction Safety Team Advisory Committee

National Institute of Standards and Technology

NIST NCST Report to Congress 2022

December 12, 2022

The Honorable Eddie Bernice Johnson, Chairwoman

House Committee on Science, Space & Technology 

Washington, D.C. 20515

Dear Madam Chairwoman,

I am pleased to submit the 2022 Annual Report of the National Construction Safety Team 

(NCST) Advisory Committee (the Committee) of the National Institute of Standards and 

Technology (NIST). The Committee serves as NIST’s advisor on implementation of the NCST 

Act (P.L. 107-231; the ‘Act’), and the opinions and recommendations expressed in this letter 

reflect our views as an independent, private sector body. This year the committee met via 

internet connection on June 8-9, and in person on Oct. 19. The meetings were used by NIST staff 

to brief the Committee on activities performed under the Act and closely related activities 

performed by NIST under other authorities. 

The Act directs that the Committee annually report our findings and recommendations to 

Congress in two areas:

1. Evaluation of NCST activities, and

2. Assessment of the implementation of recommendations of NCST and the Committee

The Act was stimulated by the World Trade Center attack in 2001. NIST distinguished itself 

with its thorough study of the performance of the affected structures and the thoughtful 

recommendations for improvements in building standards and codes that came as a result. NIST 

has a long history of investigating disasters of various types, going back at least as far as the 

1971 earthquake in the San Fernando Valley. The Act facilitates NIST’s ability to conduct such 

investigations and enhances cooperation with other federal agencies.

On August 9, 2022, a change in the Act was approved. The change requires NCST’s cooperation 

with civil litigants provided such cooperation does not compromise NCST’s investigation or 

preservation of evidence. This change is an important step forward toward timely and just 

resolution of civil suits arising from events that NCST chooses to investigate.

Finally, we applaud that NIST agrees with the recommended revisions to the NCST Act that the 

Committee has addressed to Congress: broadening the Act to include structures other than just 

buildings in those cases those structures affect the safety and resilience of the services provided 

to communities from the built environment (buildings, infrastructure and other structures). See 

the Appendix.
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National Institute of Standards and Technology

Throughout this report, we have used indented paragraphs to highlight our recommendations as 

well as those NCST activities planned over the coming year for which we expect to see 

significant progress and results.

NIST has recently signed an Inter-Agency Agreement with the National Science Foundation to 

support their Natural Hazards Engineering Research Infrastructure (NHERI) awards. 

Considering natural hazards, the aims of the NIST National Construction Safety Team and the 

NSF NHERI program are similar, minimizing the negative consequences of natural hazard 

events, although the focus of the two programs is different. The committee thinks this is a 

significant first step to leverage the studies and capabilities of each agency to further this goal. 

We recommend that NIST takes advantage of the agreement with NHERI by exploring 

more specifically how these programs can cooperate.

NIST’s Response to the 2021 Committee’s Report to Congress

NIST is to be complimented on their thorough and thoughtful responses to our recommendations.

We applaud their continued refinement of the automated scoring of events, especially the 

broadening of the damage prediction algorithm to incorporate a broad list of categories for 

measuring impact on the population, including health issues in addition to mortality rates.

We also are pleased that they are continuing to develop recommendations for construction 

guidelines for tornado effects on buildings and other structures, based on their NCST study of the 

Joplin tornadoes.

We encourage additional efforts to broaden recommendations for design guidelines for 

tornado effects to include classes of buildings and other structures in addition to highimpact buildings, to include the building code Risk Category II, which includes most

common buildings.

Their development of detailed timelines for all the projects for the Champlain Towers collapse 

study is especially welcome. This timeline is very important due to the sensitivity and public 

interest in determination of the likely sources of the collapse, and the committee believes that 

NIST has now created a realistic and thorough description of all aspects of the investigation. 

Updates to the Disaster and Failure Studies Program, including Automated Scoring of Events

Events Scoring, to measure the significance of failures or natural disasters to help determine the 

focus of investigations, is an important function. In FY2022 NIST scored 19 domestic and 

international events, comprising two tornados, eight earthquakes, two structural failures, four

building fires, two hurricanes and one wildland-urban interface fire. A few of these scored high 

but were in other countries where the lessons to be learned for the United States were judged 

minimal. One domestic event, Hurricane Ian, scored high, and a reconnaissance team has been

deployed. Based on initial findings, a determination will be made as to whether to request a full

NCST investigation. The decision must consider the potential impact on resources, since NIST 
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National Institute of Standards and Technology

currently has two NCST investigations ongoing. Hurricane Fiona in Puerto Rico did not score 

high, but due to the current investigation into Hurricane Maria, NIST will consider if aspects of 

the ongoing studies can be significantly improved with data from Fiona. 

NIST will be further developing the automated scoring method, beginning with hurricanes this 

year. They continue to explore additional means of looking at human impacts in addition to

mortality. The initial trials should help to clarify if the current methodology is adequate for their 

purposes. As previously mentioned, work on the damage prediction model should help to inform 

the human impact. The addition of a damage prediction model and the automated scoring 

algorithm, combined with input from subject matter experts, has demonstrated the ability to 

score events in anticipation of the occurrence as well as at different points of time as the event 

unfolds. NIST has used a past hurricane (Michael) in order to test the procedure, which has 

shown results that are reasonably consistent with those from human judgement. NIST is working 

on adding forecasting and wind field modeling to better assess physical damage and mortality 

predictions. Perhaps results from the Hurricane Maria Morbidity and Mortality study can be 

useful in revising this piece. Eventually, it is hoped the model can be expanded to additional 

hazards. 

The mortality and a Social Vulnerability Index (SVI) piece are still in process, and we 

look forward to seeing how the automated scoring initiative continues to improve with 

the incorporation of those pieces.

The Committee notes the excellent advancements in terms of enhanced procedures for team 

readiness, including the implementation of the Hot Team, which has pre-approval for travel and

the necessary gear set aside.

Planned additional development of processes for assessment team readiness related to 

equipment and procedures are welcome and will be followed by the Committee.

The OMB Generic Clearance for Community Resilience Data Collections was renewed on July 

27, 2022, and will expire on July 31, 2025. This renewal makes reviews of interview requests

timelier for data collection purposes, a welcome change for those processes that have been 

moving slowly in the past in several investigations.

Hurricane Maria NCST Investigation

The NIST team should be commended on the thorough job they have done in the area of hazard 

characterization for Hurricane Maria. In particular, the work on quantifying the topographic 

effect on wind speed is critical in accurately characterizing the wind profile on the island, and the 

subsequent loading induced on the buildings and other infrastructure systems. It documents an 

understanding of the wind environment and other hazards, including storm surge, rainfall, 

flooding and landslide. The approach being taken, which includes wind tunnel testing, field 

observations and measurements, and computational fluid dynamics modeling is thorough and 
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National Institute of Standards and Technology

provides the theoretical understanding of the hurricane forces. It is also good to see that 

uncertainty analysis is being considered in the hazard characterization.

We appreciate the methodological rigor that is being applied in the Hurricane Maria studies, 

including the selection of survey participants and the Mortality Study including the use of verbal 

autopsies.

NCST investigations and mortality studies in general will greatly benefit if a standard 

protocol for conducting verbal autopsies is developed.

For studies of the physical conditions of buildings and infrastructure, as well as the hazard 

characterization, they have been able to proceed without significant disruption due to the 

pandemic, relying on physical observations and interviews.

Initial observations by NCST indicated that, despite good structural performance, critical 

buildings suffered damage to the building envelope, often allowing rainwater penetration, and 

extensive nonstructural damage resulting in loss of function. Loss of function was also often 

caused by loss of power and failure of backup generators.

NCST has selected five hospitals and five schools for detailed study, including document review, 

interviews and field investigation. These studies are ongoing. Two of the selected hospitals are 

also undergoing wind-tunnel studies, with particular emphasis on gaining a better understanding 

of topographic effects.

Conclusions of the Hurricane Maria study should emphasize that loss of function, a key 

measure of resilience, is not only dependent on structural damage, but also depends on 

other building systems and surrounding infrastructure.

NIST has done an excellent job of reformatting its data processes due to the pandemic. They 

have made considerable progress in their data collection efforts especially for the morbidity and 

mortality study. The usefulness of this study is heavily dependent on the completeness of data 

collection. This will be particularly important as the differences between those interviewed and 

those not interviewed skews towards those with lower education not being interviewed. It is 

understandable that it has been more difficult to interview a next of kin of people who were 

never married. They have employed a specialized people finder service to find next of kin in the 

verbal autopsy process.

The NCSTAC is closely following the verbal autopsy effort and the use of the people 

finder service in improving these interview completion rates for the Hurricane Maria 

study.

Considerable effort has been made toward the research on public response to emergency 

communications, with much of the data collection completed and now being analyzed by the

research team. While most of the face-to-face interviews and surveys have been conducted in 
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National Institute of Standards and Technology

Spanish, translation services have been necessary for facilitating coding and analysis of some 

data sources; there may be nuances that are lost through coding in English. 

It may be useful to consult Spanish language speakers who can comment about these 

potential nuances for the Hurricane Maria study.

We are also aware of the exceptional challenges that the population of Puerto Rico experienced 

due to failures of communication and power infrastructure. The important exception was radio 

broadcast, whose transcripts could provide valuable insights into what was communicated over 

the airwaves in the days leading up to the hurricane making landfall.

The key toward successful recovery of infrastructure is resilience. The key toward resilience is to 

understand the inter dependencies of the infrastructure systems. In order to improve power, 

water, transportation and communications, a five-project component plan is underway. They are 

hazard characterization, evaluation of critical buildings, assessment of emergency 

communications, study of morbidity and mortality, and an integrative study to develop a model 

for resilience decision making. Progress has been made in reference to communication towers 

performance as a function of hazard level and code requirements. In the area of integrative study 

schools and businesses are being incorporated.

The original four representative areas in Puerto Rico have two additions, the municipalities of 

Ponce and Mayagüez for their concentration of manufacturers. Through contractor supported 

efforts the three objectives of the business and supply chain plan are advancing. Over 400 have

been completed, both in retail & services (373) and manufacturing (43); the rest will be 

completed in the summer of 2023. In addition, a shipping and transportation Interview guide has 

been developed in order to complete the analysis. 

After the Hurricane Maria data analysis is completed in the following months, NIST 

plans to develop a draft guideline that will incorporate analyses based in econometric 

modeling of recovery trajectories and SEM modeling of intended mitigation and 

adaptation behavior. The committee looks forward to learning how this development 

progresses.

Their study on the recovery of social functions will be used to advance an empirical 

understanding of long-term recovery, including measurement, identification of predictors (e.g., 

resources, characteristics associated with resilience), and exploration of interdependencies across 

the community. 

The pilot test program of methodologies to assess recovery of social functions has been 

completed (it was affected by COVID-19 limitations) and data collection has started this 

past summer. The committee looks forward to an update on this endeavor.

When looking at organizational types together, the slowest progress in restored services occurred 

with transportation (strongly affected by COVID-19 restrictions). When looking at schools and 
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National Institute of Standards and Technology

hospitals together, only slightly more than half had some form of backup for power and water 

and only a quarter had a form of backup for landline telephone.

Champlain Towers South Partial Collapse NCST Investigation

Led by Dr. Judith Mitrani-Reiser and Mr. Glenn Bell, NIST has assembled a world-class team of 

experts from NIST and elsewhere. In addition to structural, geotechnical, and materials science 

experts, the team includes experts in building codes, evidence collection, remote sensing, and 

social science. The team is committed to reliably identifying the cause of the collapse and 

recommending steps to avoid similar events. 

We commend NIST for acknowledging the value of adding social scientists to the Champlain 

Towers South investigation. 

We look forward to hearing how the addition of social scientists to the Champlain 

Towers South investigation adds to the knowledge gained from studying this tragedy. 

The team has developed and is following a comprehensive investigation plan. Key features of the 

plan include the following: 

• Collection and analysis of evidence from building records, public and surveillance video, 

social media, and eyewitness interviews;

• Site investigation including geometric surveys, subsurface testing, and structural testing of 

removed samples;

• Strategies for identifying and storing collapse remnants from the site for further study;

• Nondestructive and invasive testing of collapse remnants;

• Review of the design based on codes and methodologies in place at that time;

• Computer models capable of simulating the cause and progression of the collapse; and

• Structural testing of replicas of building elements involved in the collapse, which will allow 

for parametric study of potential contributing causes.

In addition, the social science team maintains ongoing communication to family members and 

other concerned persons who were affected by the collapse.

Testing and documentation of the collapse site are essentially complete and other aspects of the

investigation are well underway. However, the original schedule slipped considerably due to 

difficulties in procuring warehouse facilities for storing and testing collapse remnants, but a new

comprehensive timeline has been developed for the entire investigation and report production.

The advisory committee recommends careful attention to the following highly 

challenging elements of the investigation:
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National Institute of Standards and Technology

• NCST is advised to not miss out on potentially valuable information that can only be 

gained through interviews that may not be tied to physical evidence. It is also important 

to keep in mind the fact that some memories may be quite perishable over time.

• Regarding the design review, it would be very useful to find a set of calculations for a 

similar building in in South Florida designed in the late 1970s or early 1980s; such a set 

would be helpful in establishing probable design practices and the standard of care.

• With respect to the structural testing of replicas, we recommend that NCST recognize the 

uncertainty of pre-collapse conditions and conduct tests on specimens that represent a 

reasonable range of probable conditions.

• The computational models and laboratory test results should be adjusted to reflect the 

effects of long-term sustained load, which cannot be fully simulated in the laboratory 

tests.

Although the final report is not scheduled until mid-2025, overall, the advisory committee is 

highly impressed with the progress and plans to understand and learn from this tragic event.

In light of the significance of the collapse and its potential impact on the US construction 

industry, we urge NCST to expedite their investigation and issue interim summaries of 

critical lessons learned as the investigation progresses.

Implementation of Recommendations from Previous NCST Investigations

NCST reported significant progress on implementation of recommendations arising from 

previous investigations. Based on NIST proposals arising from the World Trade Center 

investigation, a draft ASCE/SEI standard on mitigation of disproportionate collapse recently

completed balloting. Also, in response to NIST recommendations, ASCE has revised wind 

tunnel testing standards and wind velocity pressure profiles. 

The most significant advances in implementation, however, arise from the Joplin tornado 

investigation. Most importantly, the ASCE tornado hazard maps and load methodology were 

unanimously approved for adoption into the 2024 International Building Code. The tornado load 

requirements are supplemented by improvements in the EF Scale, enhanced tornado field data 

collection methods, and analyses of estimated cost increases for consideration of tornado loads. 

The codification of tornado loading requirements is a significant advancement in the resistance 

of ASCE 7 Category III and IV buildings (such as hospitals and elementary schools) to EF1 and 

EF2 tornadoes, which are by far the most common. Most buildings, including the housing stock, 

are classified in Risk Category II. 

To enhance life safety for occupants of houses and ordinary buildings, and to protect 

occupants of all buildings in the event of severe tornadoes, NIST is working on 

development and implementation of sheltering strategies, shelter design and emergency 

communications. The Committee is interested in and will follow these developments.
National Construction Safety Team Advisory Committee

National Institute of Standards and Technology

Summary

NCSTAC met with NIST to review progress on initiatives over the past year and to provide 

feedback to NIST. On the basis of our discussions with NIST, we make the following 

observations:

The NCST program is highly valuable to the safety and resilience of the built environment in the 

United States.

We commend NIST for diligently administering the NCST program.

The NCST teams investigating Hurricane Maria and the Champlain Towers South collapse are 

making appropriate progress toward completion of their assignments, using comprehensive stateof-the-art investigative tools and techniques.

NIST and the NCST teams have been responsive to feedback from NCSTAC.

The Act that authorizes NIST to conduct investigations presently limits those studies to 

buildings. NCSTAC advocates for the Act be broadened to include infrastructure and structures 

other than buildings when performance of those constructions significantly impacts safety and 

resilience of services provided to communities in the United States. The specific changes that we 

recommend are contained in the appendix to this letter.

Sincerely yours,

Ross B. Corotis

Chair, National Construction Safety Advisory Committee

Attachment
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National Institute of Standards and Technology

Appendix

Proposed amendments to the NCST Act:

Sec. 2, paragraph (a):

“...after events causing the failure of a building or buildings structure that has resulted in 

substantial loss of life or that posed significant potential for substantial loss of life. Where the 

failure of the structure is the proper subject for investigation by another Federal agency, the 

Director shall defer to the authority of that agency. To the maximum extent practicable...”

And Sec. 2, paragraph (b)

“(1) PURPOSE.—The purpose of investigation by Teams is to improve the safety and structural 

integrity of buildings the built environment in the United States.

And replace the term “buildings” with “the built environment” in Sec. 2 paragraph (b)(2)(D)

And replace the term “building standards, codes, and practices” with “engineering standards, 

practices, and building codes” at the following locations:

Sec. 8 paragraph (3)

Sec. 9, paragraph (2)

Sec. 14

And replace the term “building failure” with “failure” at the following locations:

Sec. 2, paragraph (b)(2)(a)

Sec. 2, paragraph (c)(1)(G)

Sec. 2, paragraph (c)(1)(J)

Sec. 4, paragraph (a)

Sec. 4, paragraph (a)(1) [2 locations]

Sec. 4, paragraph (a)(3)

Sec. 4, paragraph (b)(a)

Sec. 4, paragraph (b)(2)

Sec. 4, paragraph (c)(1)

Sec. 4, paragraph (c)(2)

Sec. 4, paragraph (d)(3)

Sec. 4, paragraph (d)(4)

Sec. 7, paragraph (c)

Sec. 8, paragraph (1)

Sec. 8, paragraph (4)

And replace the term “building components” with “components” at the following locations:

Sec. 4, paragraph (a)(1)

Sec. 4, paragraph (a)(3)

Sec. 4, paragraph (b)(1)

And broaden Sec. 4, paragraph (d) on Interagency Priorities to include other agencies that have 

legislative mandates for the investigation of the failure of selected types of failures, such as the 

Army COE for dams and levees, the NRC nuclear power generation, the DOE for nuclear 

weapons facilities, and the DOT for vehicular bridges. [Such mandates are assumed, not 

verified, by this advisory committee]

Lastly, unrelated to the preceding, consider updating Sec. 2 paragraph (c)(1)(J) by adding a 

reference to the National Windstorm Impact Reduction Program.