Chapter A. The Loma Prieta, California, Earthquake of October 17, 1989 - Loss estimation and procedures

Abstract

The Loma Prieta earthquake caused damage to thousands of buildings and immediately created the need for hundreds of inspectors to assess these buildings for safety of occupancy or limited entry. The Applied Technology Council (ATC) had published ATC-20, "Procedures for Postearthquake Safety Evaluation of Buildings" one month before the earthquake and had held two large training seminars to introduce the book. This fortuitous introduction and distribution of the publication resulted in its wide use for the earthquake recovery. The extensive use of the ATC-20 revealed the strengths and shortcomings of its methodology. To take advantage of this assessment of the methodology by hundreds of users, the National Science Foundation funded a project to use the Loma Prieta experience to evaluate and revise ATC-20. This project, ATC-20-2: Review, "Evaluation and Revision of the ATC-20 Postearthquake Building Safety Evaluation Procedures," is ongoing. Building evaluation aspects being reconsidered or introduced include evaluation records management, format and use of posting placards and evaluation forms, asbestos in damaged buildings, "windshield" (driveby) survey evaluation procedures, agreement with related publications, structural degradation assessment, removal of goods from red-tagged buildings, repair cost estimation, and training and qualifications of the volunteers.