Makers of corrugated stainless steel tubing (CSST) and other supporters are using earthquake risk as a key argument in challenging a preliminary decision by the California Department of Housing and Community Development (HCD) not to continue recognizing CSST in the proposed 2001 edition of the California Plumbing Code.
CSST proponents cite an endorsement by Factory Mutual Research of CSST as "a viable and preferred alternative to rigid black iron piping, particularly in locations subject to considerable seismic activity." They noted the U.S. Geological Survey counted nearly 500 earthquakes (most too small to be felt) in California during a recent one-week period.