Study Details

Study Title: Safety Effects of Fixed Automated Spray Technology Systems

Authors: Veneziano et al.

Publication Date:JAN, 2015

Abstract: Fixed Automated Spray Technology (FAST) has emerged as a solution to provide quick, effective service delivery to such high-risk locations prone to icy conditions and/or with high traffic volumes. The Colorado Department of Transportation (CDOT) has installed and used FAST on bridges since 1998, with 32 units currently installed on bridges around the state. There is some concern regarding how effective they are in reducing accidents during winter weather. Previous FAST studies have considered the changes to crash occurrence following deployment, but these have been basic and compared seasonal figures or rates without accounting for site conditions. To address this shortcoming, an observational before-after study with the Empirical Bayes technique was used to determine the effect of FAST systems on crash frequencies. Results revealed that at sites where crashes were reduced, FAST systems contributed to an annual reduction of 2 percent on multilane rural highways, 16 to 70 percent on urban interstates, 31 to 57 percent on rural interstates and 19 to 40 percent on interchange ramps between interstates. However, at some sites, safety deteriorated with an increase in crashes. While the precise causes of such increases are not completely clear, they may have been the result of increased traffic, systems not being maintained properly, or systems applying fluids in improper amounts or at the wrong time. Based on the collective results, high traffic, high crash severity locations are most suitable for FAST deployments.

Study Citation: Veneziano, D., A. Muthumani, and X. Shi. "Safety Effects of Fixed Automated Spray Technology Systems". Presented at the 94th Annual Meeting of the Transportation Research Board, Paper No. 15-0756, Washington, D.C., (2015).

Comments: Some CMFs were not included given that they were based on zero crashes in before and after periods.

CMFs Associated With This Study

Category: Advanced technology and ITS

Countermeasure: Install Fixed Automated Spray Technology (FAST)

CMF CRF(%)QualityCrash TypeCrash SeverityRoadway TypeArea Type
1.57-572 StarsAllAllNot specifiedRural
1.33-332 StarsAllAllNot specifiedRural
0.9822 StarsAllAllNot specifiedRural
0.84162 StarsAllAllPrincipal Arterial InterstateUrban
0.3703 StarsAllAllPrincipal Arterial InterstateUrban
0.44563 StarsAllAllPrincipal Arterial InterstateUrban
01002 StarsAllAllPrincipal Arterial InterstateUrban
0.46542 StarsAllAllPrincipal Arterial InterstateUrban
0.42583 StarsAllAllPrincipal Arterial InterstateUrban
0.77232 StarsAllAllPrincipal Arterial InterstateUrban
0.43572 StarsAllAllPrincipal Arterial InterstateRural
0.69312 StarsAllAllPrincipal Arterial InterstateRural
1.17-172 StarsAllAllPrincipal Arterial InterstateRural
2.34-1342 StarsAllAllPrincipal Arterial InterstateRural
2.48-1483 StarsAllAllPrincipal Arterial InterstateRural
2.65-1652 StarsAllAllPrincipal Arterial InterstateRural
2.49-1492 StarsAllAllAllAll
0.6402 StarsAllAllAllAll
0.81192 StarsAllAllAllAll