A variety of composite systems, incorporating glass, carbon, and aramid fibers, and fabricated through the use of wet winding, wet layup, prepreg winding, resin infusion, or adhesive bonding of prefabricated shell sections, is being used as jackets for the seismic retrofit of columns. In the case of circular columns, the use of flat coupons for system and durability characterization does not accurately replicate field-level aspects as well as the interaction of materials and structural configuration. A jacket used for seismic retrofit is designed to confine concrete and prevent excessive dilation. NOL-ring burst tests are seen to provide a good simulation of the actual structural and load configuration for the application and are proposed as a means of characterization and durability evaluation. The paper describes results of a characterization program on four different systems, including results after laboratory and field exposure.