Earthquake Resources

Recommended Options for Improving the Built Environment for Post-Earthquake Reoccupancy and Functional Recovery Time

January 1, 2021

This FEMA P-2090/NIST SP-1254 –report provides a set of options in the form of recommendations, tasks, and alternatives for improving the built environment, which have been developed and assessed by the Committee of Experts.  It describes community resilience, defines the concepts of reoccupancy and functional recovery, and explains the relationship among these three ideas.  It explains why reoccupancy and functional recovery concepts are needed, describes a target performance state, and identifies potential cost and benefits associated with implementing enhanced seismic design.

Link to the Report fema_p-2090_nist_sp-1254_functional-recovery_01-01-2021


FEMA Releases Updated Report on Seismic Design of Rigid Wall-Flexible Diaphragm Buildings 

December 2021

FEMA’s National Earthquake Hazards Reduction Program (NEHRP) has released the updated edition of FEMA P-1026, Seismic Design of Rigid Wall-Flexible Diaphragm Buildings: An Alternative Procedure. This technical guidance document provides study results, design examples and descriptions for an alternative seismic design method for rigid wall-flexible diaphragm (RWFD) buildings. These buildings, better known as ?big box? buildings, are typically used for warehouses or retail stores and have experienced severe damage or even collapse in recent earthquakes. 

The updated report includes newly available research and numerical studies on bare-steel-deck and wood diaphragms and expands the design examples to include bare-steel-deck diaphragms.  The update also includes changes to the design procedure for consistency with the ASCE/SEI 7-22, Minimum Design Loads and Associated Criteria for Buildings and Other Structures.

The report presents an alternative design procedure for big box one-story buildings with stiff and strong vertical elements paired with flexible roof diaphragms.  The seismic performance of big box buildings is mainly related to the large displacement of flexible roof diaphragms under earthquake ground motions.

The new alternative procedure provides clear understanding of the flexible diaphragm performance that is  not properly reflected in the current traditional seismic design.  It corrects this weakness by offering increased seismic performance for big box buildings.

The target audience for FEMA P-1026 is engineers that design big box buildings.  This report gives design principles that will improve the seismic performance of big box buildings.

To download FEMA P-1026, click here.

For additional information on FEMA?s Earthquake and Wind Programs Branch and other earthquake publications, please click here.


FEMA P-2139: Short-Period Building Collapse Performance and Recommendations for Improving Seismic Design

December 30, 2020

FEMA P-2139, Short-Period Building Collapse Performance and Recommendations for Improving Seismic Design, is a four-part technical resource that provides the findings and conclusions related to this paradox.  The document recommends how to improve seismic design for short-period buildings.  It includes documents of a multi-year investigation of the response behavior and collapse performance of different structural systems to identify causes and develop solutions for short-period buildings.

The three studies presented in this series investigate three structural systems: wood light-frame, special reinforced masonry shear wall and steel special concentrically braced frame systems.  Based on the analyses of the select structural systems, the document recommends a new approach to model seismic collapse performance and ways to resolve the paradox.       

The recommendations aim to strengthen short period buildings across the nation by improving design, predicting collapse potential and enhancing building codes.  The four volumes consist of

Volume 1 – Overarching Findings, Conclusions, and Recommendations summarizes results, conclusions and recommendations from the three-system specific studies and presents a common understanding of the seismic response and collapse performance of short-period buildings.

Volume 2 – Study of One-to-Four Story Wood Light-Frame Buildings summarizes results, conclusions and recommendations from the study of wood light-frame systems.

Volume 3 – Study of One-to-Four Story Special Reinforced Masonry Shear Wall Buildings summarizes results, conclusions and recommendations from the study of special reinforced masonry shear wall systems.

Volume 4, Study of One-to-Four Story Steel Special Concentrically Braced Frame Buildings summarizes results, conclusions, and recommendations from the study of steel special concentrically braced frame systems.

To download FEMA P-2139 and for more information on FEMA’s Earthquake and Wind Program Branch click here.


2020 NEHRP Recommended Seismic Provisions for New Buildings and Other Structures

FEMA P-2082 (2020 Edition)

September 2020

FEMA is pleased to announce the release of FEMA P-2082, 2020 National Earthquake Hazards Reduction Program (NEHRP) Recommended Seismic Provisions for New Buildings and Other Structures. The release of the 2020 NEHRP Provisions marks the tenth edition of this widely recognized and reputable technical resource document since its first edition in 1985.

The NEHRP Provisions have been an essential resource for improving national seismic design codes and standards, and construction practices. Changes contained in Parts 1 and 2 of the 2020 NEHRP Provisions are expected to be considered for adoption by ASCE/SEI 7-2022 Minimum Design Loads and Associated Criteria for Buildings and Other Structures, which will be later considered for adoption by the International Building Code 2024.

Consistent with the 2009 and 2015 editions, the 2020 NEHRP Provisions includes two volumes:

Volume 1: Part 1 Provisions and Part 2 Commentary: Part 1 Provisions provides recommended changes to the seismic requirements of ASCE/SEI 7-16, Chapters 11 to 23.  Part 2 Commentary provides a complete commentary for each chapter.  It is comprised of the new commentary to each recommended change contained in Part 1 along with the existing ASCE/SEI 7-16 commentary to unchanged sections.  Listed below are some changes in the 2020 edition

  • Revised intent of the NEHRP Provisions
  • New multiperiod response spectra (MPRS) procedures and related design criteria
  • Three added new site classes
  • Updated risk-targeted maximum considered earthquake (MCER) ground motions based on the most recent 2018 USGS National Seismic Hazard Model, MPRS and updated site classes
  • Design parameters and requirements for coupled shear wall systems
  • Alternative design procedures for rigid wall-flexible diaphragm buildings
  • Updated requirements and limitations for irregularities
  • New seismic design force equations for nonstructural components
  • A concept paper on resilience-based seismic design

Volume 2: Part 3 Resource Papers: Part 3 Resource Papers include 9 individual papers.  They provide background information for some changes in Part 1 and introduce new concepts and procedures for experimental use by the design community, researchers, and standards-development and codes-development organizations. 

You may also order a hard copy of the new Provisions for free by calling the FEMA publication warehouse number 1-800-480-2520 or by emailing femapubs@gpo.gov

For more information about FEMA NEHRP, click here.


FEMA P-2091: A Practical Guide to Soil-Structure Interaction

January 19, 2020

A Practical Guide to Soil-Structure Interaction: Soil-structure interaction (SSI) can make a substantial difference in how buildings behave during an earthquake shaking and how they should be designed.  This Guide is intended to help engineers know when incorporating SSI would be important and to provide examples of how to implement different SSI techniques.  The primary target audience for the Guide is practicing engineers who are familiar with seismic design using ASCE/SEI 7 but who have little to no experience with SSI, and the focus of the Guide is on techniques that practicing engineers can use.

Link to the Guide – https://www.fema.gov/sites/default/files/documents/fema-p-2091-soil-structure-interaction.pdf


FEMA Earthquake Fact sheets


Assessing Seismic Performance of Buildings with Configuration Irregularities

September 1, 2018

This guidance evaluates current building code triggers, the influence of structural irregularities on seismic building performance (in terms of collapse probability), and the effectiveness of relevant code provisions.  The objective of the studies conducted under this project was to inform and improve U.S. codes and standards so that structures with configuration irregularities have a level of safety against collapse in an earthquake that is comparable to that for regular structures.  The publication focuses primarily on design requirements for new buildings, with limited consideration of the treatment of irregularities for existing buildings.

With a focus on irregularities that have detrimentally affected structural performance in past earthquakes or that are common in current construction trends, the project considered 12 classes of structural configuration irregularities identified in current U.S. codes and standards and two new classes as follows:

  • Torsional stiffness
  • Reentrant corner
  • Diaphragm discontinuity
  • Out-of-plane offset
  • Nonparallel system
  • Torsional strength
  • Soft story
  • Weight [mass]
  • Vertical geometric
  • In-plane discontinuity
  • Weak story
  • Weak-column/strong-beam

Download FEMA P-2012,


Safer, Stronger, Smarter: A Guide to Improving School Natural Hazard Safety

July 2022

FEMA P-1000, Safer, Stronger, Smarter: A Guide to Improving School Natural Hazard Safety equips school safety advocates and stakeholders with the information, tools, and resources they need to promote safer schools in their communities, and the guidebook aims to empower and support decision-makers by providing actionable advice.

FEMA P-1000 can help your community respond effectively and recover quickly from natural disasters.

Link to Download.


NEHRP Presents Two Publications

January 2017

The National Earthquake Hazards Reduction Program (NEHRP) of FEMA Building Science Branch is pleased to present two new publications, FEMA P-1051 CD: 2015 NEHRP Provisions: Design Examples and FEMA P-1052 CD: 2015 NEHRP Provisions: Training and Instructional Materials. These publications are developed as educational and training resources to support users of the 2015 Edition of the NEHRP Recommended Seismic Provisions for New Buildings and Other Structures (FEMA P-1050) and ASEC/SEI 7-17 Minimum Design Loads and Associated Criteria for Buildings and Other Structures.

FEMA P-1051: 2015 NEHRP Provisions: Design Examples provides selected technical design examples that apply the new methods, concepts, and procedures adopted in the 2015 NEHRP ProvisionsFEMA P-1052: 2015 NEHRP Provisions: Training and Instructional Materials provides presentations covering the new changes in the 2015 NEHRP Provisions and key points for the corresponding design examples in FEMA P-1051.  These two publications are intended for a technical audience including engineers and architects, members of the codes and standards organizations, building code professionals, research institutes, universities, material industries, and others who will benefit from a good understanding of the new changes in the 2015 NEHRP Provisions and their corresponding code changes in the upcoming ASCE/SEI 7-17.

Both publications are available to the public for download and on CD.  To access digitally, visit the NEHRP Recommended Seismic Provisions for New Buildings and Other Structures. 2015 Edition FEMA Library page.  To order CDs, contact the FEMA Distribution Center via email, FEMA-Publications-Warehouse@dhs.gov, or phone, 1-800-480-2520.

FEMA encourages design and building practices that address earthquake hazards and minimize the resulting risk of damage and injury.  The NEHRP Recommended Seismic Provisions for New Buildings and Other Structures, 2015 Edition (FEMA P-1050) is another step forward to improve the seismic safety of construction in our country.  FEMA engages with codes and standards organizations to incorporate these developments into building codes, and provides publications, such as FEMA P-1051 CD and P-1052 CD, to support best practices in engineering designs.


Rapid Visual Screening of Buildings for Potential Seismic Hazards

January 2015  

The Rapid Visual Screening (RVS) handbook can be used by trained personnel to identify, inventory, and screen buildings that are potentially seismically vulnerable. The RVS procedure comprises a method and several forms that help users to quickly identify, inven

tory, and score buildings according to their risk of collapse if hit by major earthquakes. The RVS handbook describes how to identify the structural type and key weakness characteristics, how to complete the screening forms, and how to manage a successful RVS program.
Rapid Visual Screening of Buildings for Potential Seismic Hazards: Supporting Documentation. Third Edition (FEMA P-155).  The third edition of the Supporting Documentation (FEMA P-155) describes the technical background and process used to update the Handbook and the revisions considered and conclusions reached. Extensive detail is also provided in FEMA P-155 on the third edition scoring and associated risk.


NEHRP Recommended Seismic Provisions for New Buildings and Other Structures 

The 2015 NEHRP Provisions marks the ninth edition of this technical resource document since its first publication in 1985.  FEMA is proud to sponsor this cycle of the NEHRP Provisions update, and to publish the new edition for use by national codes and standards organizations and the general public.  

The 2015 NEHRP Provisions are a new knowledge-based resource document intended to translate research results into engineering design practice. The new changes in the 2015 NEHRP Provisions have incorporated extensive results and findings from recent research projects, problem-focused studies, and post-earthquake investigation reports conducted by various professional organizations, research institutes, universities, material industries, and the NEHRP agencies. Similar to the previous edition, the 2015 NEHRP Provisions have adopted by reference the American Structural Engineers Association (ASCE) / Structural Engineering Institute (SEI) standard ASCE/SEI 7-10: Minimum Design Loads for New Buildings and Other Structures as the baseline. Order the new Provisions for free by calling the FEMA publication warehouse number 1-800-480-2520.

For more information and to download the two volume NEHRP Recommended Seismic Provisions for New Buildings and Other Structures 2015 Edition please visit: https://www.fema.gov/media-library/assets/documents/107646.