Hyatt Regency Walkway Collapse

Presentation by William J. Frey

Agenda• Case Narrative

• STS Table

• Case Chronology

• Key Decision Point

• Ethical Issue—Responsible Design

• To Engineer is Human (Video by Petroski)

• Code of Ethics Issues

Case Narrative• On July 17, 1981, the second and fourth story

walkways of the Kansas City Hyatt Regency Hotel collapsed killing 114 people and seriously injuring an additional 200.

• Cause:– “A deviation in the design in the way the rods

connected the lower skywalk to the upper and the upper to the ceiling of the atrium was clearly described and zeroed in on as the ultimate cause of the accident.” Petroski: 86

Case Narrative• Warning Signs

– The Atrium ceiling collapsed during construction; but a study carried out by an independent engineering firm found nothing wrong with the skywalk

– Workers carrying loaded wheel barrows across the skywalk complained about excess vibration and swaying

• Petroski– “After twenty months of investigation, the U.S. attorney and the Jackson

County, Missouri, prosecutor announced jointly that they had found no evidence that either a federal or state crime was committed…” (TAMU Instructor Manual)

• However in an investigation carried out by the attorney general of Missouri…– Duncan, Gillium, and GCE International Inc. were found guilty of “gross

negligence, misconduct and unprofessional conduct in the practice of engineering.” (TAMU Instructor Manual)

Chronology (Adopted from TAMU Instructor Manual Chronology)

Date EventEarly 1976

Crown Center Redevelopment Corporation begins project to build Hyatt Regency Hotel

July 1976

Gillum-Colaco, Inc. selected as consulting structural engineer

July 1976

Project enters schematic design stage

Summer 1977

GCE works with PBNDML architect to decide upon basic design

Late 1977

Bid set of structural drawings and specifications

Early 1978

Project prepared under regional building codes

ChronologyDate Event

April 4, 1978 Contract finalized between GCE and PBNDML

Spring 1978 Construction begins

August 28, 1978

Project specifications issued for construction based on AISC standards (American Institute of Steel Construction)

December 1978

Eldridge Construction Company , general contractor, finalizes subcontract with Havens Steel Company. “Havens agrees to fabricate and erect the atrium steel for the Hyatt project.”

February 1979

“Havens makes design change from a single to a double hanger rod box beam connection….” Havens claims GCE approved. GCE denies approving this.

Oct 14, 1979 Atrium roof collapse

November 1979

Seiden-Page investigates collapse and carries out “a thorough design check” of all elements of atrium roof. Assures owners of overall safety of newly designed roof.

ChronologyDate Event

July 1980 Construction of hotel completed

July 17, 1981

2nd and 4th story walkways collapse killing 114 and injuring 200.

February 3, 1984

“Missouri Board of Architects, Professional Engineers and Land Surveyors files complaint against Daniel M. Duncan, Jack D. Gillium and GCE International Inc., charginng gross negligence, incompetence, misconduct and unprofessional conduct in the practice of engineering in connection with their performance of engineering services in the design and construction of the Hyatt Regency Hotel in Kansas City, Missouri.”

November 1984

“Duncan, Gillium, and GCE International Inc. found guilty of gross negligence, misconduct and unprofessional conduct in the practice of engineering. Subsequently, Duncan and Gillum lost their licenses to practice engineering in the State of Missouri, and GCE had its certificate of authority as an engineering firm revoked. American Society of Civil Engineering (ASCE) adopts report that states structural engineers have full responsibility for design projects. Duncan and Gillum now practicing engineers in states other than Missouri.”

Component / Value

Walkway Design

Physical Surroundings

People, Groups, and Roles

Procedures Laws, Codes, Statutes

Information and Information Structures

Statics Principles

Experience with past designs

Cement FloorsRods and boltsBox beams

Atrium with 60 foot high ceiling.Three Walkways suspended from RoofLarge space below walkways on first floor

Hotel OwnerArchitecture, Engineering Design , Construction , andEngineering Investigating Firms

Professional Societies

Governmental Officials

Hotel Design ProcessEngineers signing off on plansContracting and subcont dividing responsibilityPost Accident Investigation

Engineering Codes

Contract , Civil andCriminal Law

Regulatory authority delegated to Professional Society

Post accident investigation

US attorney investigation

Trial by Missouri attn gen

Black Box: account of case in textbooks

Ease of Construction

Difficulty of constructing with original design

Designers hand off to constructers

Communication between designer and constructer

Safety Studying past failures and testing to failure

Engineers approving designInvestigating firm

Signing and Signing plans (licensed engineer)

Codes set stdsLegal system punishes violations

Elegance or Beauty

Create a “floating” walkway

Walkway to appear suspended

Concepts related to Safety and Risk

Risk AssessmentRisk Communication

Risk PerceptionRisk Management

Safety

• “A thing is safe if, were its risks fully known, those risks would be judged acceptable in light of settled value principles.” (Martin/Schinzinger, Engineering Ethics, 108)

• Safety and risk are different sides of the same coin– One is defined in terms of the other

• “Settled value principles” makes safety a matter of public policy. Government plays a role. So does business. Most importantly, so do members of the public

Public

• “those persons whose lack of information, technical knowledge, or time for deliberation renders them more or less vulnerable to the powers an engineer wields on behalf of his client or employer”– Michael Davis. Thinking Like An Engineer

• The public is in an especially vulnerable position. They stand subject to the risk. But they do not participate in the project that generates the risk

• The public has the right to free and informed consent.– This right is vulnerable if risk information does not get to them, if the

risk information is too complicated for them to appreciate, or no provisions have been taken to include them in the collective risk acceptability (=safety) decision.

Risk• The other side of the coin

– Risk and safety are correlative and defined in terms of one another

• “A risk is the potential that something unwanted and harmful may occur.” (MS 108)

• Risk has four dimensions (assessment, management, perception, and communication)

• Since risk is the probability of harm and probability implies uncertainty (lack of complete knowledge), the ethics of risk lies in how this uncertainty is communicated and distributed.– For example, does a government regulatory agency approve a product unless

it is proven harmful….– Or does it withhold approval from a product until it is proven completely safe.– In the first, the burden of uncertainty falls on the public exposed to risk, in

the second on the manufacturer who can’t reap benefits from selling the uncertainly risky product.

Risk Assessment• The scientific and exact process of determining the degree of

risk

• Animal Bioassays– Animals exposed to risk fact at intense level for short period of time– Projection from animal physiology to human physiology and from

short term/intense exposure to long term/less intense exposure

• Epidemological Studies– Comparison between populations exposed to risk and populations

not exposed to risk– Search for significantly higher risk ratio. Three-to-one not generally

significant. Six-to-one is significant

• Ethics of Risk– Since there is uncertainty in risk assessment, an ethical issue arises

as to how that uncertainty is distributed

Risk Assessment in Engineering• Fault Tree–“a diagram of the possible ways in which

a malfunction or accident can occur.”–“enable an engineer to analyze

systematically the various failure modes attendant to an engineering project”–Determining why a car won’t start by

considering different failure modes• Harris, E., Pritchard, M., and Rabins, M. (2005). Engineering Ethics: Concepts and

Cases . Thompson: 156

Risk Assessment in Engineering• Faiure Mode– “way in which a structure, mechanism, or process

can function.”

• Event Tree Analysis– “reason forward from hypothetical events to

determine what might have led to the final event”– Reasoning from pipe break in nuclear reactor to

possible outcomes (release of radiation)

– Harris, E., Pritchard, M., and Rabins, M. (2005). Engineering Ethics: Concepts and Cases . Thompson: 157

Limitations in Risk Assessment

• Cannot predict all possible failure modes

• Human error is also difficult to predict (See Reason in Human Error for a possible account)

• Probabilities assigned are largely a matter of guesswork

• “We can never be sure we have all of the possible initiating events….

• Harris, E., Pritchard, M., and Rabins, M. (2005). Engineering Ethics: Concepts and Cases . Thompson: 157-8

Different Kinds of Accident

• Normal Accidents (Perrow)– Happens in tightly coupled systems – Leads to non-linear causality– Small failure proves difficult to isolate; spreads out to create

other failures; these cascade to produced catastrophe• Complexity of system makes it difficult to predict

accident and assess risk– Ladd calls these “loss of control” accidents

• John Ladd. Bhopal Article

Human Error

• Reason treats accidents as pathogens that are latent in a complex system

• When circumstances are right, a configuration of events creates an opportunity for the pathogen to emerge

• Reason argues that accidents come from human cognitive procedures that usually work for the best

Risk Communication

• Results of risk assessment are technical and subject to different interpretations

• Public has a right to informed consent vis a vis risk– To consent to take a risk (or withhold consent) they must

understand the risk and be able to make a coherent consent decision

• This raises issues in risk communication– Clear communication– Comprehensive communication (not leaving out anything

significant)– Communication that takes into account the perspective from which

the public will perceive the risk

Risk Perception

• The public perceives risk according to a clear perspective

• This renders risk perception rational because predictable (to a certain extent)

• Factors which influence public perception of a risk’s acceptability– Voluntariness– Expected benefits– Control over risk– Minimal dread factor– Minimal unknown factor

Risk Management• Political process of determining if a certain degree of risk

is acceptable according to a community’s settled value principles

• Value principles are identified via a process of deliberative democracy which respect the meta-norms of reciprocity, publicity, and accountability

• Community’s identify small scale project for experimental analysis– These validate settled values– These also help to determine if larger scale action is acceptable

Resources• Hyatt Regency Kansas City Walkway Collapse" Online Ethics Center for

Engineering 11/24/2010 National Academy of Engineering Accessed: Thursday, December 16, 2010 <www.onlineethics.org/Resources/Cases/24338.aspx>

• Henry Petroski (1985). To Engineer is Human: The Role of Failure in Successful Design. St. Martin’s Press: 85-97.

• http://ethics.tamu.edu/ethics/hyatt/hyatt1.htm– The Kansas City Hyatt Regency Walkways Collapse – Department of Philosophy and Department of Mechanical Engineering

Texas A&M University NSF Grant Number DIR-9012252

• http://ethics.tamu.edu/ethics/hyatt/hyatt2.htm– Photos by Dr. Lee Lowry, Jr. at TAMU