Understanding the limitations and failure modes of the materials that we use is critical in maintaining a safe operating environment. The improper selection of one key component for "The Big Dig" ceiling tiles resulted in 24,000 lbs of concrete crashing down on a passing car below, killing one of the passengers on July 10, 2006. The post-accident inspection was the first in the seven years since the initial installation inspection, and the same epoxy adhesive that had failed on July 10 was found to be in the process of failing on thousands of anchor bolts used to secure other suspended concrete ceiling panels. The particular epoxy chosen was simply too weak for the tunnel application. Reduced margins, forfeited review cycles, and ignored warnings all contributed to this disaster. Given the extreme environments and new technologies employed during NASA space operations, we must ensure that all critical materials are identified and thoroughly understood through robust testing, hazard analysis, and clear documentation.