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Transportation Research Thesaurus

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Each term in the TRT is assigned a unique notational code that conveys its location within the hierarchy. The first letter of the notation represents the facet or top term. Using the notational code it is easy to determine the terms relation in the hierarchy. The term's parent (Ae) will have one less letter (from the right end) as the term (Aea). Siblings (Aeg, Aes) will have the same notational code as the term except the last letter will be different. Children (Aeac, Aeah) will have one letter appended to the end of the notational code of the term.

Hierarchical Display

Top Terms> Safety and security > Accidents

H: Safety and security
Hb: Accidents
Click to expand Hbb: Accident types
Click to expand Hbc: Accident causes
Click to expand Hbk: Accident characteristics
Click to expand Hbp: Crash phases
 Hbw: Accident analysis
Click to expand Hbx: Accident investigation

Cross Reference:
Hhge: Emergencies
Broader Term:
H: Safety and security
Related Terms:
Ha: Safety
Hh: Hazards and emergency operations
Hj: Injuries
Hk: Risk
Hm: Pathology
Hp: Medical services
Hr: Law enforcement
Hs: Security
Hu: Crimes
Hv: Criminal histories
Hw: Loss and damage
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