Auto Ignition Temperature Test Chamber Fire Investigation

摘要

During routine auto ignition temperature (AIT) testing of a solvent at the NASA White Sands Test Facility (WSTF), a fire breached the test system. The sample being tested was 99 % dodecane (C12). It was exposed to a test atmosphere of 15.7 MPa gas, meeting aviator's breathing oxygen (ABO) specifications (≥99.5 % O_2). During testing, a metal fire occurred, resulting in multiple breaches of the test system. During the event, the chamber pressure transducer mechanically burst, indicating a pressure increase of at least 159 MPa/s. This fire represented the first AIT system breach in 30 years of testing at WSTF. An investigation was undertaken to determine the cause of the breach and to propose countermeasures to prevent future mishaps. A proposed ignition scenario is presented along with an approach for preventing future incidents.