Six distinct phases of testing are involved in the masonry industry: product development, system development, production quality control, construction quality control, periodic inspections of completed projects, and investigation and evaluation of masonry problems. Each phase calls for specific types of tests that should be performed for specific reasons. MATERIALS TESTING For a project designed by traditional empirical methods, quality control testing should focus on monitoring the materials. This method inherently assumes that proper materials used in a proper manner will result in acceptable construction, particularly with respect to durability. Among the standard material specifications that might be used with the empirical design method are ASTM C 216 for clay brick, ASTM C 140 for concrete masonry, ASTM C 476 for grout, and ASTM C 270 for mortar. PERFORMANCE TESTING An alternative approach is to determine the performance required of masonry assemblages using project materials and conditions. This approach assumes that, within limits, particular material properties are subordinate to the performance properties of the finished masonry assemblage. LAB AND FIELD TESTS DIFFER Though the differences between laboratory and field conditions are significant, specifiers sometimes disregard them when specifying a testing program. A good test program reflects the differences in accuracy, environment, workmanship, curing conditions, and time constraints that exist between lab tests and field tests.