Quiet Zone Risk Index [Transportation] Law and Legal Definition
According to 49 CFR 222.9 [Title 49 – Transportation; Subtitle B -- Other Regulations Relating to Transportation; Chapter II -- Federal Railroad Administration, Department of Transportation; Part 222 -- Use of Locomotive Horns at Public Highway-Rail Grade Crossings; Subpart A – General], Quiet Zone Risk Index means “a measure of risk to the motoring public which reflects the Crossing Corridor Risk Index for a quiet zone, after adjustment to account for increased risk due to lack of locomotive horn use at the crossings within the quiet zone (if horns are presently sounded at the crossings) and reduced risk due to implementation, if any, of SSMs and ASMs with the quiet zone. The calculation of the Quiet Zone Risk Index, which is explained in appendix D of this part, does not differ for partial quiet zones.”
