Process of Elimination Credit Hours: 3 Approximate reading time: 1.5 Hours Approximate online time: 1.5 Hours You Must Be Signed In To View This Program. Register Today NFPA Documents Disclaimer- NFPA and other resource editions cited within the CFITrainer.Net site were current as of the release of the respective modules. The field of fire investigation and its guiding documents are constantly evolving and it is incumbent upon the fire investigator to remain up to date with the guidance in the current editions of the documents referenced in all modules on CFITrainer.Net, regardless of which edition was used in the writing of the module. Program Abstract The use of the process of elimination in the determination of a fire cause is a topic that has generated significant discussion and controversy in the fire investigation profession. This program uses a discussion format to introduce the concept and expand on what the 921 committee describes as negative corpus and the impact on the investigation and determination of fire cause.