Pavement Friction 

Management

Friction is a critical characteristic of a pavement that affects how vehicles 

interact with the roadway, including the frequency of crashes. Measuring, 

monitoring, and maintaining pavement friction—especially at locations 

where vehicles are frequently turning, slowing, and stopping—can prevent 

many roadway departure, intersection, and pedestrian-related crashes.

Pavement friction treatments, such as High Friction Surface Treatment (HFST), 

can be better targeted and result in more efficient and effective installations 

when using continuous pavement friction data along with crash and roadway 

data. 

Continuous Pavement Friction 

Measurement

Friction data for safety performance 

is best measured with Continuous 

Pavement Friction Measurement 

(CPFM) equipment. Spot friction 

measurement devices, like lockedwheel skid trailers, cannot safely and 

accurately collect friction data in 

curves or intersections, where the 

pavement polishes more quickly and 

adequate friction is so much more 

critical. Without CPFM equipment, 

agencies will assume the same 

friction over a mile or more. 

CPFM technology measures friction 

continuously at highway speeds and 

provides both network and segment 

level data. Practitioners can analyze 

the friction, crash, and roadway data 

to better understand and predict 

where friction-related crashes will 

occur to better target locations and 

more effectively install treatments.1

High Friction Surface Treatment

HFST consists of a layer of durable, 

anti-abrasion, and polish-resistant 

aggregate over a thermosetting 

polymer resin binder that locks the 

aggregate in place to restore or 

enhance friction and skid resistance. 

Calcined bauxite is the aggregate 

shown to yield the best results 

and should be used with HFST 

applications. 

Applications

HFST should be applied in locations 

with increased friction demand, 

including: 

• Horizontal curves.

• Interchange ramps.

• Intersection approaches.

o Higher-speed signalized and

stop-controlled intersections.

o Steep downward grades.

• Locations with a history of rear-end,

failure to yield, wet-weather, or redlight-running crashes.

• Crosswalk approaches.

Considerations

• HFST is applied on existing pavement,

so no new pavement is added.

• If the underlying pavement

structure is unstable, then the

HFST life cycle may be shortened,

resulting in pre-mature failure.

• The automated installation method

is preferred as it minimizes issues

often associated with manual

installation: human error due to

fatigue, inadequate binder mixing,

improper and uneven binder

thickness, delayed aggregate

placement, and inadequate

aggregate coverage.

• The cost can be reduced when

bundling installations at multiple

locations.

FHWA-SA-21-052

Automated application of HFST. 

Source: FHWA

HFST can reduce 

crashes up to:

for injury crashes at ramps.2

63%

for injury crashes at 

horizontal curves.2

48%

for total crashes at 

intersections.3

20%

Safety Benefits:

1 Izeppi et al. Continuous Friction Measurement Equipment as a Tool for Improving Crash 

Rate Prediction: A Pilot Study. Virginia Department of Transportation, (2016).

2 (CMF ID: 10342,10333) Merritt et al. Development of Crash Modification Factors 

for High Friction Surface Treatments. FHWA, (2020). 

3 (CMF ID: 2259) NCHRP Report 617: Accident Modification Factors for Traffic 

Engineering and ITS Improvements, (2008).

OFFICE OF SAFETY

Proven Safety 

Countermeasures

For more information on this 

and other FHWA Proven Safety 

Countermeasures, please visit 

https://highways.dot.gov/ 

safety/proven-safety-counter 

measures and https:// 

highways.dot.gov/safety/

rwd/keep-vehicles-road/

pavement-friction/hfst.