b1b4170c_cal_Agencies___FHWA_HRT_07_042__Reported_Impacts
[Agency/Location] NCHRP 346 (7) [Comments] The low level criteria evaluated used values similar to those most recently proposed. The cost factors used in the analysis reflect costs for that time period. Some costs have gone down, few materials included. Based upon a broadly gathered sample of signs. Overhead and street name signs not addressed. [Implications] Minor impact conclusion. Concluded that impact costs should not include process improvement costs. Supports long term implementation to minimize costs to agencies. Cites need for research on field methods, degradation rates, and liability issues. [Reported Impacts] 
Low level criteria will have minor impact over a 10 year implementation. Many agencies have implemented sign management processes. Cost model can be useful to assess impacts over differing sign system conditions.
Maintaining Traffic Sign Retroreflectivity: Impacts on State and Local Agencies - FHWA-HRT-07-042