Reinforcing Steel and Wire (REBAR/WWR/WIRE/SSTL/SWS)

Approximately 20 of the 50 State Departments of Transportation (DOT’s) performed some form of plant audit (a.k.a. Certification Program, Quality Monitoring Program, etc.) for the acceptance of reinforcing steel. Producing mills were subjected to several of these audits annually. Each DOT program was different and the results were not transferable from state to state. State DOT’s who performed these audits must perform an audit at each mill location requesting qualification.

A “national” program was requested by State DOT’s and the reinforcing steel industry to: “Establish a uniform procedure for approving reinforcing steel mills who furnish product for State DOT use.” The NTPEP Committee Work Plan for the Evaluation of Reinforcing Steel Manufacturers was jointly developed by the reinforcing steel bar industry and State DOT’s for this purpose. The Work Plan can be found by clicking on the Documents menu item on the NTPEP Committee Work Plan for the Evaluation of Reinforcing Steel Manufacturers was jointly developed by the reinforcing steel bar industry and State DOT’s for this purpose. The Work Plan can be found by clicking on the Documents menu item on the menu to your right.

The program begins with a review of the mill’s quality system manual (Ref.: AASHTO R 18, Section 6). The audit emphasizes:

  • The mill’s quality system – for compliance with the mill’s Quality Manual
  • The mill’s testing procedures – for compliance with the appropriate material specification (Ref.: AASHTO R 18, Section 5.4).

Next, an on-site audit is performed by the Qualification Agency. This audit reviews:

  • Production of Steel
  • Materials Traceability
  • Material Testing – on selected samples
  • Records and Mill Test Reports
  • Split Sample Testing

The annual audit determines whether the producing mill has the capabilities to consistently meet the specification (AASHTO/ASTM) requirements for the bar product produced.

Once the audit is completed, the results of the audit are reviewed. NTPEP maintains the results of the audit on their website ( NTPEP will also publish a list showing which mills have successfully met the requirements of the audit. Each DOT then determines whether the mills are approved or not based upon their established criteria (Ref.: the particular DOT’s specification).

Actual test data and/or audit reports will not be visable to the public. Audit documents can only be view by DOT representatives and the audited manufacturer. This location may also include additional information (such as: the standard sizes produced, number of furnaces, types of material produced, etc.) for use by the DOTs.

All participating mills desiring to continue under the program, will be re-evaluated on an annual basis.

A standard “audit form” has been developed for recording the results of the audit. The Audit Form is an information gathering form to be used in conjunction with worksheets, mill test reports, the mill’s Quality Manual, et cetera.

AASHTO’s Subcommittee on Materials (SOM) is comprised of the State DOT Materials Engineers and oversees the work of NTPEP. National Transportation Product Evaluation Program (NTPEP) is the Program Administrator and their Reinforcing Steel Technical Committee (comprised of representatives of several DOTs) is responsible for:

  • Evaluating the results of corrective actions taken by the producing mill (Ref. Section 5.5.3. and 5.9.)
  • Addressing modifications to the specification.

Manufacturing auditors employed by AASHTO conduct the audits for the NTPEP Audit Program.

Program Use
The program can be used as follows:

  • Only means of acceptance for reinforcing steel
  • In conjunction with job sampling and testing (as a Total Quality Assurance package).

It is anticipated that all State DOTs will use this program.

The NTPEP Technical Committee responsible for authoring the Project Work Plan convenes yearly at the NTPEP National (Annual) Meeting. During this working meeting, the Project Work Plan is discussed, changes made, and shortly thereafter balloted for adoption. Improvements are immediately implemented in the next available audit tour. When compared to other standards development exercises, the NTPEP process is agile, effective and efficient.

NTPEP Designated Lab:

  • Illinois Department of Transportation

NTPEP - Reinforcing Steel

Committee Name:
NTPEP-Technical Committee on Reinforcing Steel
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Work Plan

NTPEP audits products according to a Project Work Plan, which describes the laboratory and/or field test protocols used to conduct the evaluation. The Project Work Plan is a consensus-based document and includes peer review and input from industry experts. Each Project Work Plan is adopted after receiving at least two-thirds affirmative support from 52 AASHTO member states. The Project Work Plan is the basis for host states to conduct their testing and evaluation. When implemented by state DOTs, their own state standard specifications may supersede the NTPEP Project Work Plan. Industry is advised to be aware of state-level requirements, which may supersede basic NTPEP requirements.

Project Work Plan for Reinforcing Steel (REBAR)/Welded Wire Reinforcement (WWR) (REBAR-20-01)

User Guide

Reinforcing Steel User Guide

Audit Documents

Please visit the NTPEP Audit Documents web page for blank audit report worksheets.

Please go to NTPEP DataMine.

Please go to NTPEP DataMine.

Industry Resources

Associations that would like to be affiliated with the NTPEP Reinforcing Steel and Welded Wire Reinforcement program should contact Matt Bluman (mbluman​ for additional information.