of guardrails, barriers (including barriers between construction work zones and traffic lanes for the safety of road users and workers), and crash attenuators. (Q) The addition or retrofitting of structures or other measures to eliminate or reduce crashes involving vehicles and wildlife. (R) Installation of yellow-green signs and signals at pedestrian and bicycle crossings and in school zones. (S) Construction and operational improvements on a high risk rural road (as defined in section 148(a) of title 23, United States Code). (T) Geometric improvements to a road for the purposes of safety improvement. (U) A road safety audit. (V) Roadway safety infrastructure improvements consistent with the recommendations included in the publication of the Federal Highway Administration entitled Handbook for Designing Roadways for the Aging Population (FHWA–SA–14–015), dated June 2014 (or a revised or updated publication). (W) Truck parking facilities eligible for funding under section 1401 of MAP–21 ( 23 U.S.C. 137 note