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Bomb blast performance of glazing

The two primary aspects of glazing that characterize blast performance are

1. the level of blast load causing the glazing to initially crack or break, and
2. the retention of glass in the frame. Thus, both the performance of the frame and the glazing process are equally critical.

If glass leaves the frame, it has the potential to become a secondary hazard of the explosion. The hazard is dependent upon the size, shape and velocity of the fragments or shards, as well as the direction in which the glass is propelled. Classification guidelines for the performance of glazing during a blast event are used and defined in the diagram below and in Table 1 .

Combined ASTM F 1642/ISC Hazard Criteria Fragment Severity Rating under the ISC/GSA takes into account the final location of particles from the glazing after an explosion as seen by the arcs and numbers in the above figure. The hazard rating developed by ASTM F 1642 takes into account the fragment size, number of fragments and their final location and is depicted by the blocks of color. All dimensions are the same except for the height on the back wall which is 0.5 m (20 in) for ASTM and 0.6 m (24 in) for ISC/GSA