National Construction Safety Team Advisory Committee (NCSTAC)

Hybrid Meeting Summary

National Institute of Standards and Technology (NIST)

Gaithersburg, Maryland

June 14-15, 2023

Advisory Committee Members:

Ross Corotis, Chair University of Colorado, Boulder

Jose Izquierdo-Encarnación, Vice Chair PORTICUS

Donald Dusenberry Consulting Engineer

William Holmes Rutherford + Chekene

Gary Klein Wiss, Janney, Elstner Associates

Lori Peek University of Colorado, Boulder

Kimberly Shoaf Utah School of Medicine

Jeannette Sutton University at Albany, State University of New York

Aspasia Zerva Drexel University

NIST Leadership:

Joannie Chin Director, Engineering Laboratory

Albert Wavering Deputy Director, Engineering Laboratory

Therese McAllister Acting Chief, Materials & Structural Systems Division (MSSD)

Steven McCabe Associate Chief, MSSD

Jennifer Huergo Director of Public Affairs and Family Liaison, Champlain Towers

South NCST Investigation

NIST Staff and Associates (listed in alphabetical order):

Glenn Bell Champlain Towers South NCST Associate Lead Investigator

Tanya Brown-Giammanco Director, Disaster and Failure Studies

Maria Dillard Hurricane Maria NCST Associate Lead Investigator

Tina Faecke Designated Federal Officer

Emel Ganapati Champlain Towers South NCST Project Leader

David Goodwin Champlain Towers South NCST Project Leader

James Harris Champlain Towers South NCST Project Leader

Kenneth Harrison Hurricane Maria NCST Project Leader

Youssef Hashash Champlain Towers South NCST Project Leader

Jennifer Helgeson Hurricane Maria NCST Project Leader

Georgette Hlepas Champlain Towers South NCST Project Leader

Kenneth Hover Champlain Towers South NCST Project Leader

Katherine Johnson Hurricane Maria NCST Project Leader

Scott Jones Champlain Towers South NCST Project Leader

Marc Levitan Hurricane Maria NCST Project Leader

Joseph Main Hurricane Maria NCST Lead Investigator

Judith Mitrani-Reiser Champlain Towers South NCST Lead Investigator and Hurricane

Maria NCST Project Leader

Jack Moehle Champlain Towers South NCST Project Leader

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Sissy Nikolaou Champlain Towers South NCST Project Leader

Fahim Sadek Champlain Towers South NCST Project Leader

Kamel Saidi Champlain Towers South NCST Project Leader

Christopher Segura Champlain Towers South NCST Project Leader

Jonathan Weigand Champlain Towers South NCST Project Leader

DongHun Yeo Hurricane Maria NCST Project Leader

Public Speakers:

Martin Langesfeld

Pablo Langesfeld

I. Welcome and Opening Remarks

Ms. Tina Faecke, serving as the Designated Federal Officer (DFO), called the meeting to order

and noted that nine Committee members attended in person, and one member was absent. She

informed everyone the meeting would be recorded. Ms. Faecke then introduced the NIST

Engineering Laboratory Director, Dr. Joannie Chin, who welcomed the Committee and thanked

them for their engagement and participation. She noted the importance of the Committee, and

highlighted key objectives for the agenda. She noted how recommendations from previous

NCST investigations have led to lasting changes in building codes, standards, and practices.

II. Review of Meeting Goals

Committee Chair, Dr. Ross Corotis, described the meeting goals.

● Review NIST’s response to the NCSTAC’s 2022 Report to Congress,

● Review Disaster and Failure Studies program scoring of events and readiness of teams,

● Describe new disaster research initiatives,

● Review progress on the implementation of NCST investigation recommendations for the

World Trade Center and the Joplin tornado,

● Review the status of the NCST investigation of Hurricane Maria’s effects on Puerto Rico,

● Review the status of the NCST investigation of the partial collapse of Champlain Towers

South in Surfside, Florida, and

● Develop the Committee’s annual report to Congress

The Disaster and Failure Studies Director, Dr. Tanya Brown-Giammanco, then reviewed the

agenda, which was modified to have Ms. Rebecca Hermanowicz provide the Federal Advisory

Committee Act ethics briefing after the Disaster and Failure Studies program updates.

III. NIST Response to the NCSTAC’s 2022 Report to Congress

Dr. Brown-Giammanco provided a brief overview of the NCST Act and the Committee’s

responsibilities under the NCSTAC Charter of 2020. She then provided a summary of each of the

seven recommendations the Committee provided in their annual report, along with a NIST

response to each. The presentation can be found here:

NIST Response to the NCSTAC’s 2022 Report to Congress

Discussion: The Committee and NIST staff discussed tornado-resistant design or safe rooms for

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existing construction, the addition of social scientists to the Champlain Towers South NCST,

communications with families of the Champlain Towers South victims in advance of Committee

meetings, and scoring of events and data collection.

IV. Disaster and Failure Studies (DFS) Program Updates

Dr. Brown-Giammanco presented an overview of the DFS Program and the progress made since

the October meeting. She highlighted the Committee’s composition, and noted that two members

would complete their second terms in July, while another three would complete their second terms

in September. She then introduced Dr. Lori Peek as the newest member, and mentioned efforts are

underway to recruit additional members. She then summarized a $40M disaster supplemental

provided to NIST by Congress in the omnibus budget in December 2022 to conduct disaster

studies. She also highlighted recent disaster events that had been scored, and provided an overview

of a preliminary reconnaissance mission conducted for the February 2023 Turkey-Syria

Earthquakes. The presentation can be found here:

Disaster and Failure Studies Program Updates

Discussion: The Committee and NIST staff discussed the challenges with converting learnings

from studies and investigations into changes to building codes and standards, performance

expectations and education of engineers, and safety monitoring and training for deployed team

members, as well as the need for a top-down approach to safety culture and a focus on emotional

health of deployed team members. The Committee’s role regarding the Hurricane Ian study and

potential follow-on areas of study for the 2023 Turkey earthquake was reviewed.

V. Annual Ethics Briefing

Ms. Rebecca Hermanowicz from the Department of Commerce Ethics Law and Programs Office

gave the annual briefing on ethics rules for Special Government Employees, and thanked the

Committee for completing their annual online financial disclosure forms.

VI.Hurricane Ian Study Overview

The National Windstorm Impact Reduction Program (NWIRP) Acting Director, Mr. James LaDue,

provided an overview of the impacts of Hurricane Ian. He described the wind speed measurements

and wind field, which were below the design wind speed, as well as wind damage noted during the

preliminary reconnaissance mission in October 2022. He also described the surge and associated

damage, as well as damage from rainwater intrusion. He concluded his presentation by describing

the newly-launched NWIRP study goals. The presentation can be found here:

Hurricane Ian Study

Discussion: The Committee and staff discussed the need to include social scientists in risk

communications research and challenges that result from potential loss of perishable data. They

also discussed the differences in high water data collected by various agencies, and possible

challenges with getting people to evacuate from high water and obtaining perspectives of

emergency responders.

VII. Summary of Progress on Previous Investigations

Dr. Fahim Sadek provided an update about the progress made on implementing the

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recommendations from the World Trade Center NCST investigation. He described the recent

completion of a recommendation to develop a disproportionate collapse standard, which was

published as American Society of Civil Engineers (ASCE) 76-23 in May 2023. He described the

overall impacts that have been made as a result of the 30 World Trade Center NCST investigation

recommendations, which include dozens of changes to codes and standards in the International

Building Code (IBC), International Fire Code (IFC), the National Fire Protection Association

(NFPA) Life Safety Code and Uniform Fire Code , and the ASCE standards. With the new

disproportionate collapse standard, all of the recommendations resulting from the World Trade

Center NCST investigation have been completely implemented.

Dr. Marc Levitan provided an update about the progress made on implementing the

recommendations from the Joplin Tornado NCST investigation. He described efforts to impact

codes and standards for existing construction, especially as it relates to retrofitting to install

tornado shelters. He described progress in standardizing the Enhanced Fujita (EF) Scale through

data collection from the Quad-State Tornado of December 2021, which included: further testing of

the science-based, probabilistic Smart^DI tool that has been previously reported on; and analysis

utilizing the treefall wind speed estimation method that was pioneered in the Joplin Tornado NCST

investigation. He also described recent successes in tornado-resistant designs being adopted in

model codes and local regulations, including inclusion in the 2023 Florida Building Code, approval

to be included in the 2024 National Fire Protection Association 5000 Building Construction and

Safety Code, and the continuing process for adoption into the 2024 International Building Code.

He discussed a design guide for ASCE 7-22 tornado loads and interim guidance for

tornado-resistant design and retrofit of residences, both of which were published in collaboration

with FEMA. He also summarized impacts and engagements, as well as remaining tasks associated

with implementing the recommendations from the Joplin Tornado NCST investigation.

The presentations can be found here:

Summary of Progress on Prior NCST Investigations

Discussion: The Committee and staff discussed individual community efforts to adopt

tornado-resistant design requirements, challenges with getting tornado shelter requirements to be

adopted, and the perception that schools and other critical facilities are not frequently affected by

tornadoes. They discussed the need for communications and consideration of social and political

science disciplines that may influence decision making with regard to tornado protection. They

also discussed the development of the new disproportionate collapse standard and why it was

developed as a stand-alone standard and not incorporated into ASCE 7, and the need for

standardization of wind tunnel testing recommended by the World Trade Center NCST

investigation.

VIII. Hurricane Maria NCST and NWIRP Updates

- Summary of Hurricane Maria NCST Investigation Progress

Prior to the presentations, the DFO asked if any members of the Committee had a conflict of

interest and if so, to recuse themselves. No Committee members recused themselves. Dr. Joseph

Main then provided a summary of the Hurricane Maria Program, including both the NCST

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investigation and NWIRP study projects. He described the program goals, and reviewed the

supporting contracts and collaborations that are contributing to the program. He described the

panel discussion format that the team would use in the meeting to describe cross-cutting themes in

the Program, provided an overview of key datasets collected thus far, as well as key stakeholder

engagement and new team member additions. The presentation can be found here:

Summary of Hurricane Maria NCST Investigation Progress

Discussion: The Committee and staff discussed the discrepancy between the number of

deaths initially attributed to Hurricane Maria in Puerto Rico, the number reported days later, and

the official death toll accepted by the Governor. They also discussed the new additions to the

Hurricane Maria team and points of contact for power infrastructure interviews and surveys. They

discussed the plan for data dissemination following the conclusion of the investigation.

- Cross-Project Panel Theme 1: Hospitals

Dr. Main provided an introduction to the first Hurricane Maria panel session, focusing on hospitals.

He described the motivation and integration of data streams and analyses. Dr. DongHun Yeo then

described recent progress on understanding the hazard exposure and specifically wind tunnel

testing and modeling efforts for the Hospital Bella Vista. Dr. Main then described damage

observations at hospitals, and data curation and processing for wind tunnel testing of two hospitals.

Dr. Judith Mitrani-Reiser concluded the presentation by describing data obtained from the verbal

autopsy and socio-environmental survey developed for the investigation. She also described

preliminary observations from hospital function surveys that support mortality assessment. The

presentation can be found here:

Hurricane Maria Cross-Project Panel Theme 1: Hospitals

Discussion: The Committee and staff discussed the challenges hospitals faced with regard

to staffing in the immediate aftermath of the hurricane, the granularity of infrastructure damage

data, efforts to pre-register those with medical needs that rely on power, baseline and

hurricane-related mortality statistics, the demographic and geospatial data collected in the mortality

project, and what recommendations could result from the investigation.

- Cross-Project Panel Theme 2: Sheltering

Dr. Maria Dillard introduced the second Hurricane Maria panel session on sheltering, describing

the motivation and integration of data streams and analyses. Dr. Katherine Johnson then described

pre-storm and during storm messages about sheltering, as well as the primary data sources. She

described information related to sheltering obtained from surveys, as well as evacuation behavior

determined from survey respondents. Dr. Levitan then described common themes observed during

Phase 1 evaluations of shelters. He showed an example damage matrix for a shelter building and

highlighted the benefit of using the matrix across the investigation. Dr. Dillard provided an

overview of the performance of schools, which often served as shelters during Hurricane Maria.

She highlighted locations where schools participated in the Wave 1 survey for the Recovery of

Social Functions Project. She also showed an example damage matrix for a school. The

presentation can be found here:

Hurricane Maria Cross-Project Panel Theme 2: Sheltering

Discussion: The Committee and staff discussed data sources for shelter occupancies given

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the communications challenges following the hurricane, and challenges associated with

determining exactly what facilities served as shelters, especially given Hurricane Irma’s previous

landfall on September 7, 2017. They also discussed demographics of shelter occupancy. They

discussed the communications associated with “strong shelters” and the meaning in Puerto Rico

that those are concrete buildings, which all formal shelters were, how this ties to the need for

understanding local Spanish translation nuances, and how there are also parallels with language

used for communicating the need for sturdy shelters during tornadoes. They also discussed shelter

mortalities, especially given duration of occupation, and cross-project data collection efforts, as

well as the lack of structural considerations in selecting shelter or best-available refuge shelters.

Potential recommendations associated with emergency communications and the need to understand

the baseline building characteristics were also discussed.

- Cross-Project Panel Theme 3: Infrastructure Dependencies

Dr. Dillard introduced the final Hurricane Maria panel session on infrastructure dependencies, and

described the motivation and integration of data streams and analyses. Dr. Kenneth Harrison then

described the role of infrastructure and damage to wireless communications, power, and

transportation. He described how the infrastructure supported shelters, hospitals, schools, and

businesses, which are each key themes within the Hurricane Maria Program. Dr. Dillard then

described questions in the verbal autopsy and socio-environmental questionnaire that address the

impact of infrastructure disruption on mortality, and showed a relationship between average days

without power and the total deaths that occurred within 14 days of landfall. Dr. Jennifer Helgeson

closed the presentation by describing the role of infrastructure in the recovery of businesses,

education, and healthcare facilities. She showed the percentage of businesses that participated in

the study, as well as a matrix for critical infrastructure disruption and preparedness as they relate to

businesses. She also highlighted the duration without power for four areas of Puerto Rico, which

exceeded 100 days in many regions. The presentation can be found here:

Hurricane Maria Cross-Project Panel Theme 3: Infrastructure Dependencies

Discussion: The Committee and staff discussed the confidence in preliminary results,

survey response rates and distribution for businesses, and contact methods for business interviews.

They also discussed Hurricane Maria’s impacts on the water system and the need to clarify the

specific functions that were lost. They discussed the data collected, the timeline for additional data

collection, and the ability to demonstrate the uncertainty in the data in the final reports.

- Conclusion and Update on Hurricane Fiona

Dr. Dillard concluded the Hurricane Maria Program presentations by providing an overview of

datasets collected to date, and those that are in progress, for both the NCST and NWIRP projects.

She provided an update on the program’s timeline and described efforts to understand the impacts

of Hurricane Fiona, which made landfall on September 18, 2022, on the ongoing recovery from

Hurricane Maria. The team has begun to include Hurricane Fiona-related interview questions and

surveys, specifically for the Critical Buildings and Recovery of Social Functions projects, and has

extended some staffing and is pursuing two new contracts. The presentation can be found here:

Conclusion and Update on Hurricane Fiona

Discussion: The Committee and NIST staff discussed an upcoming contract to facilitate

development of the Hurricane Maria reports. They also discussed integration of questions related to

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Hurricane Fiona into ongoing Hurricane Maria survey and interview efforts. They discussed the

potential for buildings and infrastructure to have been weaker during Fiona due to previous damage

from Maria, but also the possibility of them being stronger due to mitigation between the two

events which could inform the development of recommendations. They discussed the ongoing

challenges with the power infrastructure in Puerto Rico.

IX.NCSTAC Preparation of Annual Report to Congress

The Committee discussed the approach to prepare their annual report to Congress, as well as initial

writing assignments.

Ms. Faecke adjourned the Day 1 portion of the meeting at approximately 5:00 pm ET.

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NCSTAC HYBRID MEETING SUMMARY – Day Two

June 15, 2023

Ms. Faecke, serving as the DFO, called the Day 2 meeting to order and noted that nine members

of the Committee were in attendance in person, and one member was absent. She reminded

everyone the meeting would be recorded.

X. Champlain Towers South NCST Updates

- Champlain Towers South NCST Investigation Introduction and Summary

Dr. Mitrani-Reiser opened the presentation by providing an acknowledgement of the lives lost in

the Champlain Towers South partial collapse. She then provided background information on the

NCST Act. She described what NIST can and cannot do under the NCST Act authorities. She

provided an overview of highlighted activities since the October 2022 meeting. She also described

the organization of the investigation team to support evaluation of failure hypotheses. She

described recent efforts to develop a layout and move many of the evidence specimens to a new

primary evidence facility to allow for safe invasive testing. She highlighted efforts to find the DVR

of the building’s security system, and non-destructive and destructive testing that had recently been

completed. The presentation can be found here:

Champlain Towers South NCST Investigation Introduction and Summary

Discussion: The Committee discussed the concurrent investigation by Miami-Dade Police

and the expanded acquisition authorities expiring September 30, 2023 that are limited to the

Champlain Towers South investigation. They discussed obstacles faced by the investigation,

particularly those associated with acquisition regulations and the potential pursuit of legislative

changes in the NCST Act. They also discussed the collection of perishable data and evidence.

- Cross-Project Panel Theme 1: Evidence Collection, Measurements, and Visualization

Dr. Mitrani-Reiser introduced the panel, and Dr. Sissy Nikolaou then described some of the history

of the Champlain Towers South site, including geologic and development information. Dr.

Christopher Segura then described observations and measurements made on the physical evidence

specimens and efforts to understand as-built and pre-collapse conditions. Dr. Jonathan Weigand

highlighted pool deck conditions, including maintenance activities over the life of the building, as

well as measurements and survey data. Dr. Emel Ganapati described social science data collection

efforts through interviews, highlighted innovative techniques being used, and noted that some

information on the progressive collapse not previously available had been collected using these

methods. The presentation concluded with Dr. Georgette Hlepas describing the team’s development

of data management systems and visualization tools to help evaluate failure hypotheses. The

presentation can be found here:

Champlain Towers South Cross-Project Panel Theme 1: Evidence Collection, Measurements, and

Visualization

Discussion: The Committee and staff discussed efforts to match time-stamped videos,

photographs, and other electronic data with interview data. The Committee suggested that once the

investigation is complete, the team write methodological-based papers on the cognitive interview

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techniques and the combined social science and engineering approach to the investigation. They

also discussed the spacing of reinforcement in the evidentiary debris and how to convey this

information graphically, as well as survey measurements, additional desired datasets and how plans

are adjusted based on data that were able to be obtained versus those that were not. Implications of

the 40-year recertification inspection, and additional layers added to the pool deck were also

reviewed.

- Cross-Project Panel Theme 2: Materials, Geotechnical, and Structural Analysis and

Testing

Mr. Glenn Bell introduced the second panel, and described work on conducting structural code

checks. He showed a diagram of locations where the design strength of slab-column connections

on the pool deck did not meet the original code and highlighted locations with moderate and severe

understrength. Dr. Kenneth Hover then described efforts to develop a concrete mix design for use

in laboratory testing. He described aggregate proportions and sizes, as well as water-to-cement

ratios and implications for service life and durability. Next, Dr. Scott Jones described recent

invasive coring work, mechanical tests that are underway, as well as preliminary observations from

petrographic analysis of the concrete. Dr. Youssef Hashash then presented information on

geotechnical analyses and testing to evaluate subsurface soils and the soil-structure interactions in

the foundation. He described efforts to model the interactions using three-dimensional finite

element models. The presentation concluded with Dr. Fahim Sadek describing progress in the

collapse analysis modeling and analysis of potential failure initiation scenarios. The presentation

can be found here:

Champlain Towers South Cross-Project Panel Theme 2: Materials, Geotechnical, and Structural

Analysis and Testing

Discussion: The Committee and staff discussed load conditions for the pool deck, code

checks, design checks and overlays, collapse conditions, concrete characteristics, and consideration

of creep and time dependent effects. The Committee suggested that degradation of tensile strength

over time be considered. The punching shear capacity of the slab as well as creep and shrinkage

effects were described. The boundary conditions, depth, water level, and the number of layers

incorporated for the three-dimensional model of the soil-structure interaction was discussed.

- Cross-Project Panel Theme 3: Failure Hypotheses Development and Evaluation

Dr. Mitrani-Reiser introduced the final Champlain Towers South panel. Dr. David Goodwin then

described the recently-developed failure hypothesis database and the associated workflow for

evaluating each hypothesis. Dr. Kamel Saidi then described different remote sensing and data

visualization techniques and datasets that support the analyses of failure hypotheses. Dr. Jack

Moehle described how failure initiation and progression hypotheses are evaluated and provided a

few examples of specific hypotheses. Next, Dr. Mitrani-Reiser described the various points in the

lifetime of the building leading up to the collapse, the kinds of data available at each phase and

how they are evaluated in the context of failure hypotheses. The presentation concluded with Dr.

James Harris describing potential topics and areas for recommendations to be developed as a result

of the investigation. He highlighted specific building standards that may be appropriate to seek to

change. The presentation can be found here:

Champlain Towers South Cross-Project Panel Theme 3: Failure Hypotheses Development and

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Evaluation

Discussion: The Committee and staff discussed the analysis of the collapse progression

timeline, as well as the ability of local jurisdictions to evaluate building designs and potential need

for peer review. Quality control and assurance, and requirements for retention of design drawings,

as they relate to investigation recommendations were also discussed. Implications of climate

change, scientific communication of the investigation, and possible extraordinary loading

mechanisms were discussed.

- Concluding Remarks and Next Steps

Mr. Bell concluded the Champlain Towers South sessions by revisiting key takeaways from each

of the panel presentations. He reinforced preliminary results regarding the pool deck evaluation,

and provided additional information about misplaced reinforcement and above-design loading

caused by heavy planters with palm trees being placed on the pool deck throughout its lifetime. He

described additional fill and pavers that were added after the initial construction, corrosion of slab

and column reinforcement, and how these factors combined to result in critically low margins

against failure. He also described next steps for each of the six technical projects, as well as an

updated investigation timeline. He concluded the presentation with an acknowledgement of the

lives lost, complexity of the investigation, and the need to get the technical work right. The

presentation can be found here:

Concluding Remarks and Next Steps

Discussion: The Committee and staff discussed the possibility of finding an initiating

mechanism versus the possibility that long-term degradation of the structure lead to the collapse.

They also discussed details surrounding punching shear and reinforcement, as well as the

relationship between the timeline and budget.

XI. Public Input

Ms. Faecke opened the public comment period. Mr. Martin Langesfeld, family member of Nicole

Langesfeld who was killed in the Champlain Towers South collapse, spoke and described his

concerns about the pool deck not being constructed to code, with the slow pace of the

investigation, and that the collapse site will have a new building constructed prior to NIST

completing its investigation. Mr. Pablo Langesfeld, also a family member of Nicole Langesfeld,

spoke of frustrations about not knowing the reason for the collapse and the need for families to

gain closure.

XII. Closing Remarks

Dr. Joannie Chin, gave the closing remarks. She thanked the NIST staff who organized the

meeting, as well as the Committee members for their participation and advice. She presented an

appreciation letter and certificate of recognition to Mr. Gary Klein and Dr. Jeannette Sutton for

their service on the Committee, and noted this was their last meeting. She also announced that Dr.

Kimberly Shoaf agreed to be the Vice Chair beginning in October, when Mr. Pepe

Izquierdo-Encarnacion would assume the Chair role following the end of Dr. Ross Corotis’s term.

Dr. Chin also highlighted the progress made for each of the ongoing investigations as well as in the

implementation of recommendations from previous investigations. She acknowledged the

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dedication and hard work of the investigation teams, and acknowledged the difficulty for those

waiting for answers from the investigations. She concluded by encouraging members of the public

to continue to submit data and information to the NIST disaster data portal.

XIII. NCSTAC Preparation of Annual Report to Congress

The Committee used the remainder of the meeting time to revisit the draft writing assignments and

discussed a timeline for submission of draft materials. They discussed the need to reach consensus

during the September 7, 2023 meeting.

Following the Committee’s discussion, Ms. Faecke adjourned the meeting at approximately 3:30

pm ET.

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