Unreinforced masonry building

[3] In California, the 1933 Long Beach earthquake resulted in a near-immediate statewide ban on construction of new unreinforced masonry school buildings and the Field Act.

[3][4] Retrofits are generally intended to prevent injury and death to people, but not to protect the building itself.

[3] According to the 2006-04 California seismic safety commission report, there are still 7800 URM buildings with no retrofitting in the state, including 1100 in the city of Los Angeles.

Compliance took many years,[5] and as of 2008, most (but not all) of the unreinforced masonry buildings in San Francisco have undergone retrofitting.

The Wasatch Front has a population of 2 million, and contains 200,000 UMBs compared with the entire state of California's 25,000.