Risk Management Series Design Guide for Improving Hospital Safety in Earthquakes, Floods, and High Winds FEMA 577 / June 2007 About the Cover Olive View Hospital Replacement Fares Well In 1994 Quake The new Olive View hospital building shown on the cover performed well during the 1994 Northridge earthquake. This quake, of the same magnitude as the 1971 San Fernando Earthquake that nearly collapsed the original building, caused no serious damage. Built in 1970, the Medical Treatment and Care Building of the Olive View Hospital complex was designed to meet the earthquake provisions of building codes in place at that time. The hospital incurred heavy damage (at left) during the 1971 earthquake and was subsequently rebuilt to stricter design and construction standards. [Photo] Olive View Hospital After the 1971 Magnitude 6.7 San Fernando Earthquake Photo Credit: E.V. Leyendecker, U.S. Geological Survey FOREWORD AND ACKNOWLEDGMENTS BACKGROUND The United States is currently in the middle of the biggest hospital construction boom in more than 50 years. According to data from the U.S. Census Bureau, spending for construction of new hospitals and other medical facilities increased 65 percent between 2000 and 2006. New scientific and technological innovations, as well as advancements in medical practice and the organization of health care, demand a physical environment different from the hospitals of the past. This de­mand is being met by the increasing use of evidence-based design, which relies on a combination of scientifically proven research and the evaluation of completed projects to make design and construction decisions that improve the safety and functionality of hospital buildings. Architects and engineers now look at credible research related not just to structural and mechanical engineering, but also to clinical outcomes, behavioral science, the environment, and technology. New building designs are now seen as important components that can improve medical outcomes, patient safety, employee satisfaction, and even financial performance. The effective use of evidence- based design requires continuous and timely updates of the information that affects hospital design. As part of this effort, the Federal Emergency Management Agency (FEMA) has developed this Design Guide to provide the designers of new hospitals and retrofits to existing ones with the latest information and research results on the best practices to reduce the risks from natural hazards. This publication is the latest addition to FEMA’s Risk Management Series, which provides guidelines for mitigating the risks associated with multiple hazards. The series emphasizes mitigation best practices for specific building uses and occupancies, such as schools, critical facilities, commer­cial buildings, and multi-family dwellings. OBJECTIVE AND SCOPE The objective of the “Design Guide for Improving Hospital Safety in Earthquakes, Floods, and High Winds” is to inform and assist design professionals, hospital administrators, and facility managers in implementing sound mitigation measures that will decrease the vulnerability of hospitals to disruptions caused by natural hazard events. The intent of the Design Guide is to provide its audience with state-of-the-art knowledge on the variety of vulnerabilities faced by hospitals exposed to earthquakes, flooding, and high-winds risks, as well as the best ways to mitigate the risk of damage and disruption of hospital operations caused by these events. The information presented in this publication provides an exhaustive review of mitigation measures and design solutions that can improve the safety of hospitals in natural hazard events. However, this publication is not intended to be a comprehensive mitigation design manual that the reader can use to develop actual plans and specifications. It is intended as an introduction to the fundamental principles of natural hazard risk reduction, with an emphasis on mitigation planning and the design of hospital buildings. The information presented here is intended to help design professionals, hospital administrators, and facility managers understand the broad aspects of risk reduction methods and strategies, and integrate them into hospital designs. ORGANIZATION AND CONTENT The Design Guide is organized around three specific natural hazards: earthquakes, floods, and high winds. It comprises four main chapters. Chapter 1 presents an overview of the principal considerations determining hospital design, from standard industry requirements to new developments that are transforming both hospital operations and organization of the physical environment. It highlights the known vulnerabilities of hospitals and the repercussions of damage caused by natural hazard events that frequently interfere with the operation of these facilities. The chapter concludes with a look at the multi-hazard approach to hospital design, and provides basic guidelines on the interaction between the re­sponses of building components to various natural hazard risks. Chapter 2 examines potential earthquake damage to hospitals, and how these facilities can most efficiently improve their performance. The chapter opens with an introductory discussion on the nature and prob­ability of earthquakes, and procedures for determining seismic risk to specific locations. Typical seismic damages, and the possible resulting effects on building functions or risk to occupants, are described and related to the standard damage states currently used in performance-based earthquake engineering design. The chapter ends with a review of the best practices in seismic design and seismic retrofit of hospital facilities. Chapter 3 discusses the nature of flood forces and their effects on buildings. It outlines the procedures for risk assessment and describes the current mitigation measures for reducing flood damage. It emphasizes the benefits of avoiding construction of new hospitals in high-risk areas, describes regulatory design requirements that help reduce the exposure of hospitals that must be located in flood hazard areas, and encourages the application of appropriate mitigation measures to existing hospitals at risk of flooding. Chapter 4 discusses the effects of wind forces on hospitals’ structural and nonstructural building components. By reviewing numerous examples of wind- induced damage to these facilities, this chapter highlights the best mitigation practices for new hospital design and construction, and for the rehabilitation of existing facilities. It concentrates on the building components that are the most critical for maintaining uninterrupted operation of hospitals, and provides detailed guidelines for improving their design and construction. At the end are Appendix A, which contains a list of acronyms, and Appendix B, which contains a glossary of terms that appear in the Design Guide. ACKNOWLEDGMENTS Principal Authors: Christopher Arnold, Building Systems Development, Inc. William B. Holmes, Rutherford and Chekene Rebecca C. Quinn, RCQuinn Consulting, Inc. Thomas L. Smith, TLSmith Consulting Bogdan Srdanovic, URS Corporation Wilbur Tussler, Consultant Contributors: Milagros Nanita Kennett, FEMA, Project Officer, Risk Management Series Publications Eric Letvin, URS Corporation, Project Manager Susan Patton, URS Corporation Rob Fernandez, URS Corporation Ivy Porpotage, URS Corporation Wanda Rizer, design4impact Project Advisory Panel: Amar Chaker (AEI), American Society of Civil Engineers (ASCE) Ken Dickerman, AIA Academy of Architecture and Health Skip Gregory, Florida Agency for Health Care Administration Mike Kuechenmeister, American Society of Healthcare Engineering Jim Rossberg (SEI), American Society of Civil Engineers (ASCE) John Sullivan, Portland Cement Association This manual will be revised periodically, and FEMA welcomes comments and suggestions for improvements in future editions. Please send your comments and suggestions via e-mail to: RiskManagementSeriesPubs@dhs.gov TABLE OF CONTENTS FOREWORD and Acknowledgments i Background i Objective and Scope ii Organization and Contents ii Acknowledgements iii 1 HOSPITAL DESIGN CONSIDERATIONS 1-1 1.1 Introduction 1-1 1.2 Health Care Industry 1-3 1.2.1 Ambulatory Care 1-3 1.2.2 Patient Volume 1-4 1.2.3 Aging Facilities 1-5 1.2.4 Healing Environments 1-5 1.2.5 Technological Advances 1-6 1.3 Hazard Mitigation 1-8 1.3.1 Assessing Risk 1-9 1.3.2 Evacuation Considerations 1-10 1.3.3 Potential Vulnerabilities 1-11 1.3.3.1 Structural Vulnerability 1-12 1.3.3.2 Nonstructural Vulnerability 1-12 1.3.3.3 Spatial and Other Organizational Vulnerabilities. 1-15 1.4 Hospital Design and Construction 1-17 1.4.1 Building Codes 1-18 1.5 Multi-Hazard Design Considerations. 1-20 1.5.1 The Need for a Multi-Hazard Approach 1-21 1.5.2 Multi-Hazard Design Matrix 1-22 1.6 References. 1-32 2 MAKING HOSPITALS SAFE FROM EARTHQUAKES 2-1 2.1 Introduction 2-1 2.1.1 The Nature and Probability of Earthquakes 2-1 2.1.2 Earthquake Effects 2-2 2.1.3 Measuring Earthquake Effects 2-3 2.1.3.1 Measuring Seismic Ground Motion 2-5 2.1.3.2 Measuring Potential for Liquefaction 2-7 2.1.3.3 Measuring Potential for Landslide2-7 2.1.3.4 Measuring Potential for Tsunami and Seiche 2-8 2.1.4 Earthquakes: A National Problem 2-8 2.2 Seismic Building Design 2-11 2.2.1 The Equivalent Lateral Force (ELF) Analysis Methodology 2-12 2.2.1.1 Acceleration 2-13 2.2.1.2 Amplification and Soil Type 2-14 2.2.1.3 Building Period 2-15 2.2.2 Critical Building Characteristics 2-16 2.2.2.1 Period and Resonance 2-16 2.2.2.2 Damping 2-16 2.2.2.3 Nonlinear Behavior 2-17 2.2.2.4 Ductility 2-17 2.2.2.5 Strength and Stiffness 2-18 2.2.2.6 Drift 2-19 2.2.2.7 Configuration: Size and Shape 2-20 2.2.2.8 Stress Concentrations 2-20 2.2.2.9 Torsional Forces 2-21 2.2.3 Specifications for Performance-Based Seismic Design 2-24 2.2.3.1 Performance Levels 2-24 2.2.3.2 New Developments in Performance-Based Design 2-27 2.3 Earthquake Damage to Hospitals 2-29 2.3.1 Types of Structural Damage 2-31 2.3.1.1 The Case of the Olive View Medical Center 2-32 2.3.2 Nonstructural Damage 2-35 2.3.2.1 The Case of New Olive View Medical Center 2-39 2.3.2.2 The Case of Kona Community Hospital, Hawaii 2-42 2.3.3 Consequences of Building Damage 2-48 2.3.4 Seismic Vulnerability of Hospitals 2-49 2.3.4.1 Seismic Vulnerability of Hospitals Based on Historical Performance in California. 2-50 2.3.4.2 Vulnerability Assessment of Hospital Buildings 2-52 2.3.4.3 Comparability of Hospital Buildings 2-53 2.4 Risk Reduction Measures 2-57 2.4.1 Site Selection Basics. 2-57 2.4.2 Seismic Design Basics 2-58 2.4.3 Structural Systems 2-59 2.4.3.1 Basic Types of Lateral Force Resisting Systems 2-59 2.4.3.2 Innovative Structural Systems 2-62 2.4.3.3 Structural Systems Selection 2-63 2.4.4 Nonstructural Components and Systems 2-64 2.4.4.1 Code Regulated Nonstructural Systems 2-65 2.4.4.2 Interstitial Space for Utility Installations 2-67 2.4.5 Mitigation Measures for New Buildings 2-68 2.4.5.1 The Case of Loma Linda Veterans Hospital 2-68 2.4.6 Mitigation Measures for Existing Buildings 2-72 2.4.6.1 Procedures and Design Strategies for Rehabilitation of Structural Systems 2-72 2.4.6.2 The Case of Naval Hospital Bremerton 2-73 2.4.6.3 Procedures and Design Strategies for Rehabilitation of Nonstructural Systems 2-77 2.4.6.4 Summary of Risk Reduction Measures for Existing Buildings 2-77 2.5 Checklist for Seismic Vulnerability of Hospitals 2-80 2.6 References and Sources of Additional Information 2-84 3 MAKING HOSPITALS SAFE FROM FLO0DING 3-1 3.1 General Design Considerations 3-1 3.1.1 The Nature of Flooding 3-1 3.1.2 Probability of Occurrence or Frequency 3-4 3.1.3 Flood Characteristics and Loads 3-7 3.1.3.1 Hydrostatic Loads 3-9 3.1.3.2 Hydrodynamic Loads 3-10 3.1.3.3 Debris Impact Loads 3-12 3.1.3.4 Erosion and Local Scour 3-13 3.1.4 Design Parameters 3-14 3.1.4.1 Flood Depth 3-14 3.1.4.2 Design Flood Elevation 3-17 3.1.4.3 Flood Velocity—Riverine. 3-17 3.1.4.4 Flood Velocity—Coastal 3-18 3.1.5 Flood Hazard Maps and Zones 3-19 3.1.5.1 NFIP Flood Maps 3-20 3.1.5.2 NFIP Flood Zones 3-21 3.1.5.3 Coastal A Zones 3-24 3.1.6 Floodplain Management Requirements and Building Codes 3-26 3.1.6.1 Overview of the NFIP 3-26 3.1.6.2 Summary of the NFIP Minimum Requirements 3-28 3.1.6.3 Executive Order 11988 and Critical Facilities 3-29 3.1.6.4 Scope of Model Building Codes and Standards 3-30 3.2 Hospitals Exposed to Flooding 3-33 3.2.1 Identifying Flood Hazards at Existing Hospitals 3-33 3.2.2 Vulnerability: What Flooding Can Do to Existing Hospitals 3-33 3.2.2.1 Site Damage 3-34 3.2.2.2 Structural Damage 3-36 3.2.2.3 Nonstructural Damage 3-38 3.2.2.4 Medical Equipment 3-41 3.2.2.5 Utility System Damage 3-41 3.2.2.6 Contents Damage 3-44 3.3 Requirements and Best Practices in Flood Hazard Areas 3-47 3.3.1 Evaluating Risk and Avoiding Flood Hazards 3-47 3.3.2 Benefits and Costs: Determining Acceptable Risk 3-48 3.3.3 Site Modifications 3-50 3.3.4 Elevation Considerations 3-53 3.3.4.1 The Case of Boulder Community Foothills Hospital, Boulder, Colorado 3-58 3.3.5 Dry Floodproofing Considerations 3-63 3.3.6 Flood-Resistant Materials 3-66 3.3.7 Access Roads 3-68 3.3.8 Utility Installations 3-69 3.3.9 Potable Water and Wastewater Systems 3-71 3.3.10 Storage Tank Installations 3-71 3.3.11 Accessory Structures 3-72 3.4 Reduction for Existing Hospitals 3-73 3.4.1 Introduction 3-73 3.4.2 Site Modifications 3-73 3.4.3 Additions 3-75 3.4.4 Repairs, Renovations, and Upgrades 3-77 3.4.5 Retrofit Dry Floodproofing 3-78 3.4.5.1 The Case of Pungo District Hospital, Belhaven, North Carolina 3-79 3.4.6 Utility Installations 3-84 3.4.7 Potable Water and Wastewater Systems. 3-86 3.4.8 Other Damage Reduction Measures 3-87 3.4.9 Emergency Measures 3-88 3.5 Checklist for Building Vulnerability of Flood-Prone 3-90 3.6 References and Sources of Additional Information 3-98 4 MAKING HOSPITALS SAFE FROM HIGH WIND 4-1 4.1 General Design Considerations 4-1 4.1.1 Nature of High Winds 4-3 4.1.2 Probability of Occurrence 4-3 4.1.3 Wind/Building Interactions 4-5 4.1.4 Building Codes 4-9 4.1.4.1 Scope of Building Codes 4-9 4.1.4.2 Effectiveness and Limitations of Building Codes 4-10 4.2 Hospitals Exposed to High Winds 4-13 4.2.1 Vulnerability: What High Winds Can Do to Hospitals 4-13 4.2.1.1 Types of Building Damage 4-13 4.2.1.2 Ramifications of Damage 4-16 4.2.1.3 The Case of West Florida Hospital, Pensacola, Florida 4-17 4.2.2 Evaluating Hospitals for Risk From High Winds 4-24 4.2.2.1 New Buildings 4-24 4.2.2.2 Existing Buildings 4-25 4.3 Requirements and Best Practices In High-Wind Regions 4-26 4.3.1 General Hospital Design Considerations 4-26 4.3.1.1 Site 4-28 4.3.1.2 Building Design 4-29 4.3.1.3 Construction Contract Administration 4-34 4.3.1.4 Post-Occupancy Inspections, Periodic Maintenance, Repair, and Replacement 4-35 4.3.1.5 Site and General Design Considerations in Hurricane-Prone Regions 4-36 4.3.2 Structural Systems 4-37 4.3.2.1 Structural Systems in Hurricane-Prone Regions 4-41 4.3.3 Building Envelope 4-42 4.3.3.1 Exterior Doors 4-42 4.3.3.2 Exterior Doors in Hurricane-Prone Regions 4-46 4.3.3.3 Windows and Skylights 4-47 4.3.3.4 Windows and Skylights in Hurricane-Prone Regions 4-49 4.3.3.5 Non-Load-Bearing Walls, Wall Coverings, and Soffits 4-52 4.3.3.6 Non-Load-Bearing Walls, Wall Coverings, and Soffits in Hurricane-Prone Regions 4-64 4.3.3.7 Roof Systems 4-65 4.3.3.8 Roof Systems in Hurricane-Prone Regions 4-74 4.3.3.9 The Case of DeSoto Memorial Hospital, Arcadia, Florida 4-81 4.3.4 Nonstructural Systems and Equipment 4-85 4.3.4.1 Exterior-Mounted Mechanical Equipment 4-86 4.3.4.2 Nonstructural Systems and Mechanical Equipment in Hurricane-Prone Regions 4-94 4.3.4.3 Exterior-Mounted Electrical and Communications Equipment4-94 4.3.4.4Lightning Protection Systems (LPS) in Hurricane-Prone Regions4-97 4.3.4.5 The Case of Martin Memorial Medical Center, Stuart, Florida 4-102 4.3.5 Municipal Utilities in Hurricane-prone Regions 4-104 4.3.5.1 Electrical Power 4-104 4.3.5.2 Water Service 4-105 4.3.5.3 Sewer Service 4-106 4.3.6 Post-design Considerations in Hurricane-Prone Regions 4-106 4.3.6.1 Construction Contract Administration 4-106 4.3.6.2 Periodic Inspections, Maintenance, and Repair 4-106 4.4 Remedial Work on Existing Facilities 4-107 4.4.1 Structural Systems 4-109 4.4.2 Building Envelope 4-111 4.4.2.1 Sectional and Rolling Doors 4-111 4.4.2.2 Windows and Skylights 4-112 4.4.2.3 Roof Coverings 4-115 4.4.3 Exterior-Mounted Equipment 4-117 4.4.3.1 Antenna (Communications Mast) 4-117 4.4.3.2 Lightning Protection Systems 4-118 4.4.4 The Case of Baptist Hospital, Pensacola, 4-118 4.5 Best Practices in Tornado-Prone Regions 4-122 4.5.1 The case of Kiowa County Memorial Hospital, Greensburg, Kansas 4-126 4.5.2 The case of Sumter Regional Hospital, Americus, Georgia 4-135 4.6 Checklist for Building Vulnerability of Hospitals Exposed to High Winds 4- 141 4.7 References and Sources of Additional Information 4-147 APPENDICES Appendix A Acronyms A-1 Appendix B Glossary of Terms B-1