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Federal Highway Administration Research and Technology
Coordinating, Developing, and Delivering Highway Transportation Innovations

This report is an archived publication and may contain dated technical, contact, and link information
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Publication Number:  FHWA-HRT-17-047    Date:  September 2017
Publication Number: FHWA-HRT-17-047
Date: September 2017


Appendix D. Frequently Asked Questions

  1. How long will the assessment take? For every panel member, the assessment involves two parts: (1) the independent work of reviewing the technology and documenting the TRL recommendation; and (2) the group work of discussing and reconciling different reviewers’ perspectives of the technology. The time required for each step will depend on the complexity of the technology, the richness of the data available on it, and the objectives of the review. Simpler technologies take less time to review, especially if no critical decisions will be made based on the scoring discussion. At a minimum, expect several hours to review background documents or participate in a presentation about the project results and several hours to discuss and come to a consensus on the TRL. For larger, multiyear projects, expect to spend 1 day or more reviewing background information and a half-day or more participating in an assessment panel.

  2. When working through the TRL Scale, do I have to start at TRL 1? No. If you have a technology that the group believes is fairly close to implementation, you may select a higher TRL and move forward. You might also find it useful to work backward instead. However, if time allows, a high-level review of the earlier TRLs may be very useful in orienting the team and possibly in identifying gaps in the research.

  3. For TRL 4: Is an “integration plan” a plan for integrating the technology into the operations of the organization? No. In the context of the TRL, “integration plan” describes how the technology’s components will interface and work together to make the technology system operational.

  4. For TRL 7: Say we have a technology that is clearly at TRL 7 by nearly all counts. Does the fact that we never really did laboratory testing mean that we should call it a TRL 4? That does not make sense. No. If laboratory testing was not considered necessary and, instead, the technology development team went straight to prototype testing in a nonlaboratory environment, that does not mean that the technology is necessarily at TRL 4. However, it does raise the question of what lessons might have been learned if laboratory testing had been conducted and could point to a need for additional testing.

  5. For TRL 8: How well must a technology perform to confirm that it meets “its stated purpose and functionality as designed?” To meet this criterion, the technology must operate as designed under typical and stress-test conditions.

  6. For TRL 8: If target performance measures were never clearly defined or documented, does that mean that TRL 8 has not been achieved? Target performance measures are metrics that describe the intended functionality of the technology. If “desired performance” was defined only loosely, then technologies that meet that vaguely defined state can achieve TRL 8.

  7. For TRL 9: How broadly must the technology be adopted to reach TRL 9? This will vary considerably depending on the goals of the project. Broad adoption is not required.




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