General

You are here

In-Service Performance Evaluation Resources (ISPE)

Federal Highway Administration Pilot In-Service Performance Evaluation of Guardrail End Treatments

The Federal Highway Administration (FHWA) Office of Safety Research and Development is conducting a pilot in-service performance evaluation (ISPE) of the most widely used energy absorbing guardrail end terminals (GETs) in the United States, specifically: ET-Plus, ET-2000, Flared Energy Absorbing End Terminal (FLEAT), Slotted Kinking Terminal (SKT), Manual for Assessing Safety Hardware Slotted Kinking Terminal (MSKT), X-Lite, X-Tension, and Soft Stop. For each device, the evaluation will address:

  • Crash performance in terms of vehicle occupant risk.
  • The sensitivity to varying effects such as environmental conditions, site characteristics, and impact conditions.
  • The degree of sensitivity to improper installation, maintenance and repair.

Data are being collected at test sites in four States that have agreed to participate in this pilot study: Massachusetts, Pennsylvania, California, and Missouri. This work is being done in cooperation with the National Highway Traffic Safety Administration (NHTSA), the Resource Center's Safety Technical Services Team, the Office of Safety and the division offices in each of the data collection States. The study is not collecting data across the entire State. The pilot study is only collecting data in a few State-selected regions. NOTE: Crash data collection indicates association with guardrail end terminals, not causality. 

Detailed onsite investigations are being performed for fatal and serious injury producing crashes, generally within 24 hours of receiving notification of the crash, by NHTSA's Special Crash Investigation teams. The division offices, in cooperation with their State department of transportation (DOT) partners, are collecting data for the minor and property-damage-only (PDO) crashes.

Data collection is currently scheduled to run to 2019. Based on the number of crashes expected and based on historic trends, the current timeframe for completion will likely be insufficient to collect enough data to draw statistically significant conclusions about the safety performance of the devices. However, the study will identify current challenges to conducting effective in-service performance evaluations and recommend best practices for 1) the collection of real-time data on crashes involving roadside safety hardware, 2) interagency communication at the State level regarding crash reporting, and 3) data management regarding hardware maintenance and inventory.

Data collection consists of photographs and forms. Subject matter experts can use the information from the photographs and forms for analysis. The tables below include data from the State-designed collection areas and do not reflect all guardrail and end terminal data across the entire State.

*Reporting Period through October 31, 2018.

Crash Type Distributions by State*

StateCoordinating AgencySerious/FatalPDO/
Minor
Pilot Study Start DateFull Study Start Date
CaliforniaCaltrans41097/1/20161/25/2017
MassachusettsMassDOT24775/24/20165/24/2016
MissouriMoDOT469411/13/201511/13/2015
PennsylvaniaPennDOT9892/15/20162/15/2016
PennsylvaniaPTC5225/1/20165/1/2016
Totals, by Severity88391  
Aggregate Total479 

Crash and End Terminal Distributions*

Crash
Type
Trinity Highway Products, LLCRoad Systems, Inc.Lindsay CorporationTotal
ET-
2000
ET-
Plus
Unk
ET-
Plus
4"
ET-
Plus
5"
Soft
Stop
FLEATSKTMSKTX-
LITE
X-
Tension
Max-Tension
PDO211290279169946600344
Minor4514210101100047
Serious9014290134160168
Fatal0181023050020
Total341812632191812599701479

Note:  Serious/Fatal crashes are disaggregated as fatal until the final crash report is produced. This will account for crash-related fatalities occuring within 30 days.

Crash and End Terminal Distributions by Agency Partners*

Agency/
Partner
Trinity Highway Products, LLCRoad Systems, Inc.Lindsay CorporationTotal
ET-
2000
ET-
Plus
Unk
ET-
Plus
4"
ET-
Plus
5"
Soft
Stop
FLEATSKTMSKTX-
LITE
X-
Tension
Max-Tension
Caltrans/
MAIT/SCI
011001001004
Caltrans20248074212500109
MassDOT/
CARS
10600002140124
MassDOT002510064410077
MoDOT/
SCI
80122909240046
MoDOT121381110015070094
PennDOT/
SCI
001101501009
PennDOT11161690232030089
PTC/
SCI
002000201005
PTC00100714000022
Total341812632191812599701479

Notes: Types of data coding adjustments include the following.         

  • Reclassification of end terminals or injury severity, based upon additional documentation submitted by partners.
  • Deletion, based upon arrival of additional information, such as: subject matter experts may find that cases do not qualify because the photographed end terminal was repaired, and there is no documentation of what existed before a crash; redundant case information; or subject matter experts may find that the damaged end terminal was not an energy absorbing design and therefore not included in this study.     
  • Disqualification, based upon a non-passenger vehicle impact, such as farm vehicles and tractor trailers, for which the end terminals are neither designed nor tested.
     

Project Manager and Point of Contact

Ana Maria Eigen, D.Sc
FHWA Office of Safety Research and Development
ana.eigen@dot.gov

Updated: Friday, November 9, 2018