Local Agency Programs Guardrail Standards

The Michigan Department of Transportation (MDOT) Local Agency Program (LAP) has sunset the use of National Cooperative Highway Research Program (NCHRP) 350 guardrail devices on LAP projects with the conclusion of Fiscal Year 2022.

All projects are now required to use Manual for Assessing Safe Hardware (MASH) compliant guardrail devices.

The 2020 MDOT Standard Specifications for Construction, the Frequently Used Special Provisions, the 2020 Pay Item list, and the MDOT website have eliminated reference to the NCHRP devices.

Local Agencies are not required to upgrade guardrail to MASH compliant devices on projects unless the devices are being replaced.  

Please refer to the R-60-Series Special Detail for details on height transitions such as Type B rail to Type 2M Terminal, or MSG-8 rail to type 1B/2B/3B terminals at MDOT Special Details Index (state.mi.us).

Also, please note that there are several Type 2M terminals available and the lengths are not consistent.  The MDOT guardrail calculation sheet determines guardrail length based on the shortest terminal length.  Therefore, it is recommended to provide the station at the location between the terminal and the start of the tangent run only (no station at the end of the terminal).

Please contact Ryan Doyle at DoyleR3@Michigan.gov with any questions.