AASHTO issues updates to MASH guidance AASHTO issues updates to MASH guidance Pam / Wednesday, March 25, 2020 0 8722 Article rating: 5.0 The American Association of State Highway and Transportation Officials (AASHTO) issued an update to its guidance for the Manual for Assessing Safety Hardware (MASH) on Tuesday. The newly published information provides three additions to the Frequently Asked Questions for MASH. Read more