The San Francisco Board of Supervisors has passed an ordinance amending the Existing Building Code. This ordinance mandates an assessment of the city's inventory of seismically vulnerable Rigid-Wall-Flexible-Diaphragm (RWFD) and Concrete Buildings. It also adopts voluntary seismic retrofit standards for these structures. The Code Advisory Committee (CAC) and the Building Inspection Commission (BIC) both unanimously recommended approval of the ordinance with proposed amendments. The legislation aims to enhance public safety and improve the city's ability to recover from a major earthquake by identifying at-risk buildings and providing a framework for voluntary seismic upgrades. This proactive measure addresses the potential for catastrophic damage and collapses of older concrete buildings during seismic events.