Virginia Transportation Research Council (VTRC) (2004). The Safety Impacts of Differential Speed Limits on Rural Interstate Highways (Report No. FHWA-HRT-04-156). United States. Federal Highway Administration. https://rosap.ntl.bts.gov/view/dot/41591
Virginia Transportation Research Council (VTRC). The Safety Impacts of Differential Speed Limits on Rural Interstate Highways. Report no. FHWA-HRT-04-156. United States. Federal Highway Administration, 2004. https://rosap.ntl.bts.gov/view/dot/41591.
Virginia Transportation Research Council (VTRC) The Safety Impacts of Differential Speed Limits on Rural Interstate Highways. United States. Federal Highway Administration, 2004, Report no. FHWA-HRT-04-156, ROSA P. https://rosap.ntl.bts.gov/view/dot/41591.
When federal law permitted individual States to raise speed limits from 55 mi/h (88 km/h) to 65 mi/h (105 km/h) on rural interstate highways, some States uniformly raised their speed limits for passenger cars and trucks while other States raised the speed limit for passenger cars only, leaving the truck speed limit at 55 mi/h (88 km/h), which created a Differential Speed Limit (DSL). When the national maximum speed limit was repealed, States had further flexibility in setting their speed limits. By 2002 several States had experimented with both DSLs and Uniform Speed Limits (USLs). The Federal Highway Administration sponsored a study to investigate the effect of USLs and DSLs on vehicle speeds and crashes on rural interstates nationwide. This TechBrief briefly summarizes the findings of that study. Overall, the study was not able to isolate or measure the effect of USL/DSL changes. Speed characteristics were generally unaffected by a USL or DSL policy. No consistent safety effects of DSL as opposed to USL were observed within the scope of the study.
Virginia Transportation Research Council (VTRC) (2004). The Safety Impacts of Differential Speed Limits on Rural Interstate Highways (Report No. FHWA-HRT-04-156). United States. Federal Highway Administration. https://rosap.ntl.bts.gov/view/dot/41591
Virginia Transportation Research Council (VTRC). The Safety Impacts of Differential Speed Limits on Rural Interstate Highways. Report no. FHWA-HRT-04-156. United States. Federal Highway Administration, 2004. https://rosap.ntl.bts.gov/view/dot/41591.
Virginia Transportation Research Council (VTRC) The Safety Impacts of Differential Speed Limits on Rural Interstate Highways. United States. Federal Highway Administration, 2004, Report no. FHWA-HRT-04-156, ROSA P. https://rosap.ntl.bts.gov/view/dot/41591.
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