A "grandfather clause" allows certain steel gas pipelines to operate at hoop stress levels above 72 percent of the specified minimum yield strength (SYMS) of the pipe-the highest operating hoop stress permitted on steel pipe in all other regulated gas pipelines. The grandfathered pipelines may not provide as much protection against stress-related failures as lines constructed more recently in similar locations. OPS is concerned about this possible disparity in protection, and invites public participation in determining an appropriate course of action regarding the "grandfather clause.