High tension cable guardrail shall meet the requirements of Section 2505 of the Standard Specifications.  Approved sources are listed in the Materials Approved Products Listing Enterprise (MAPLE).



Acceptance of high tension cable guardrail will be on the basis of approved sources and certification from the manufacturer. Samples of materials may be obtained from projects to verify compliance with the specifications. Approved sources are in Appendix A.


The certification statement shall include the following:


1.     All materials meet the manufacturer’s specifications as tested under NCHRP Report 350 criteria and comply with the applicable specifications of the Iowa Department of Transportation.


2.     All steel and iron materials meet the requirements of IM 107, Group 2, Buy America.



Application for approval shall be sent to the Methods Engineer in the Office of Design, 515-239-1402. All relevant documentation, product literature, brochures and any other details along with the FHWA approval letter stating compliance to NCHRP 350 shall be submitted. Samples of materials may also be requested for evaluation.


The following are minimum requirements to be considered for approval:


  1. Meet the requirements of NCHRP Report 350, Test Level 4 criteria (6:1 slopes) and Test Level 3 criteria (4:1 slopes)


  1. Be accepted as a crash worthy device by the FHWA


  1. Exhibit a dynamic deflection for NCHRP Report 350 Test 3-11 of 8 feet (2.4 m) or less