Section 503B — DEFINITIONS

For the purpose of Chapters 5B and 5C, certain terms are defined as follows:

BOLTS-PLUS is the installation of shear and tension anchors at the roof and floors and, when required, the bracing of the unreinforced masonry bearing walls upon evaluation of the height-to-thickness ratio of these walls.

POOR SOIL is all soil lying bayward of the line indicating the landward limit of Bay Mud deposits as shown on the U.S. Geological Survey Map MF-1376, title “Map Showing the 200-feet thickness contour of surficial deposits and the landward limit of Bay Mud deposits of San Francisco, California,” by William B. Joyner, 1982.

EXCEPTION: A building need not be considered as being located on poor soil when a subsurface exploration demonstrates that the soil is not underlain by Bay Mud.

U NREINFORCED MASONRY BEARING WALL BUILDING is a building or structure having at least one unreinforced masonry bearing wall.