NOTEWORTHY PRACTICE 

KENTUCKY HIGH FRICTION SURFACE TREATMENT (HFST) 

Systemic Installations of High Friction Surface Treatments 

on Small Curves in Kentucky 

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 What was the safety issue, problem, or gap? 

When typical low-cost safety improvements, such as signing and delineation, do not reduce crashes, the 

Kentucky Transportation Cabinet’s (KYTC) options are limited. Narrow, winding roads are prevalent in 

Kentucky and lane widths less than 9 feet are not uncommon. In many instances roads have very little 

right-of-way, making more substantial treatments like shoulder installation very costly. While striping is a 

viable solution in some circumstances, the Manual on Uniform Traffic Control Devices (MUTCD) does not 

recommend installing center or edge line pavement markings for pavement widths under 20 feet. 

These challenges directed KYTC to look for alternative countermeasures to keep vehicles on the road 

coupled with an ability to be installed within a constrained right-of-way. High friction surface treatments 

(HFST) emerged as a potential alternative to address Kentucky’s issues. 

 What were the key challenges that needed to be addressed before the new 

practice could be implemented? 

KYTC had vast experience identifying, selecting, and installing HFST on long and large radii curves. The 

agency had yet to install small HFST applications and wanted to test its viability to be introduced at 

curves on the minor road system. Since small applications could likely lead to increased installations 

costs associated with small quantities and equipment mobilization, KYTC needed to identify a means to 

successfully and efficiently address the dozens of sites. 
2012
 

70+% KYTC installs small HFSTs 2011 

15 HFSTs Resulting in Crash (less than 800 square yards) 2010 Reduction 

2009 

NOTEWORTHY PRACTICE 

KENTUCKY HIGH FRICTION SURFACE TREATMENT (HFST) 

Describe the new practice: 

From 2009 through 2012, KYTC installed 15 small – less than 800 square yards – 

HFST applications on State routes to test the feasibility of small installations on 

minor routes by bundling several small installations into a single contract. 

Key accomplishments, including roadway safety 

improvements: 

The small applications at various sites around the State led KYTC to realize that, 

not only can HFST have a role in reducing crashes on the minor road system, but 

it is even feasible to systemically implement the treatment using an identification 

and selection process similar to the one used on major roads. This process 

involves quantifying crash history as the initial determining factor, then ensuring 

that pavement quality is sufficient to accept the treatment and provide durability 

over the HFST’s life span. 

What technical and/or institutional changes resulted from 

the new practice? 

KYTC recognized that the same benefits HFST afforded at long or large radii 

curves could be extended to the minor system on smaller curves. The agency 

bundled small installations in regional proximity into a single project for the 

bidding process, maximizing benefits while minimizing costs. 

What benefits were realized as a result of the practice? 

At the 15 sites where small HFST applications were installed, KYTC noted a greater 

than 70 percent crash reduction overall. At several sites, the HFST application 

attributed to zero crashes in the five year after period. 

FOR MORE INFORMATION 

Joseph Cheung Tracy Lovell 

FHWA-SA-16-057

http://safety.fhwa.dot.gov FHWA Office of Safety 

joseph.cheung@dot.gov 

Kentucky Transportation Cabinet

tracy.lovell@ky.gov