1.   Diagnoses are based on evidence accumulated about failure modes, operator observations of symptoms and historical records.

2.   Vital to such Decisions is a clear understanding of system functions, failure modes and the consequences of failure.

3.   A process for hazard identification where all known failure modes of components or features of a system are considered in turn and undesired outcomes are noted.

4.   Despite the findings, McGrew said the newly discovered failure mode was not necessarily related to temperature.

5.   These included developments in new materials and construction methods, material characteristics, and failure modes.