Roadside Safety Hardware Identification Methods

Executive Summary

Section 1429 of the Fixing America’s Surface Transportation (FAST) Act requires the Secretary of Transportation to study identification methods that can improve the capability of transportation agencies to collect data about their roadside safety hardware, such as guardrail and end treatments. Transportation agencies use the collected data to evaluate the in-service performance of this safety hardware. This report submits the results of the study, which include:

• Determining available roadside safety hardware identification (ID) methods.
• Conducting an in-depth analysis of the ID methods.
• Evaluating the ID methods for their ability to convey information, withstand roadside conditions, and connect to existing agency systems.

Proper installation, maintenance, and evaluation of roadside safety hardware ensure that the hardware performs as designed and tested. Laboratory crash testing is only the first step in addressing the safety of roadside hardware. The Federal Highway Administration (FHWA) and the American Association of State Highway and Transportation Officials (AASHTO) encourage States to perform in-service performance evaluations (ISPE) to identify real-world performance of roadside hardware. Creating an inventory and monitoring the field performance of safety hardware provide in-service performance data that supplement data obtained from crash-testing the hardware. Transportation agencies can effectively improve their capability to monitor the field performance of safety hardware by using ID methods for ISPE programs or as part of overall agency asset management systems:

• The ISPE programs determine and document how the safety feature performs during a broad range of collision, operational, and maintenance situations for a typical site and traffic conditions.⁽¹⁾ The ISPE of roadside safety hardware provides additional information to practitioners on how hardware performs under various field conditions, which vary widely from the conditions under which the hardware is crash-tested.
• Asset management is a strategic and systematic process of operating, maintaining, and improving physical assets. Asset management allows analysis of collected data to aid in making decisions about maintenance, preservation, repair, rehabilitation, and replacement actions.⁽²⁾

This report documents the evaluation of ID methods and investigates how these ID methods may be integrated into a transportation agency’s ISPE or asset management framework. Currently available ID methods were identified based on the FAST Act Section 1429 requirement, input from the expert panel, and review of literature and specifications. The FHWA identified and studied three primary ID methods:

• Barcodes, either one-dimensional (1D) or two-dimensional (2D).
• Radio frequency identification (RFID) devices, either active or passive.
• Serial numbers.

Approaches to tracking, and evaluating the performance of assets using these ID methods were also investigated, with a focus on roadside assets where that information was available.

Barcode and RFID systems include the tag identifier, readers or scanners to read the information, and middleware or software to store the information. System performance depends on line of sight, reading rate, reading distance, tag size, use of metal, and use near water. Serial numbers can be read and data entered manually. They can be stamped directly on roadside safety hardware or printed on a tag identifier. Practitioners in the highway industry were consulted about factors and characteristics that would impact their selection of ID methods. These factors covered a broad range of issues, including the components of the hardware to be identified, information security, placement and vandalism of ID tags, durability, and compatibility with existing systems. Evaluation of the ID methods took these factors into account and applied a grading system for various performance aspects. Approaches to gathering and using data from the devices were graded based on ease of use; available tag identifier options and technologies; and the ability to convey information, withstand roadside conditions, and connect to existing agency systems.

The transportation field and other industries have successfully used barcode, RFID, and serial number tag identifiers as an ID method. However, examples of use for safety hardware are very limited, and no full-scale ISPE programs were identified. There are currently four States with pilot ISPE programs that include a limited sample of guardrail terminals. While other experiments or research on ISPE has been conducted, very little progress has been made in this area. This could be due to the magnitude of implementing such a system in the field. The following factors should be evaluated when considering the use of hardware ID methods: connectivity to existing agency data systems, the number and categories of roadside hardware devices, the type of ID device, and the cost associated with the implementation of the ID devices and the supporting readers and software.