2021 Standard Specifications 2021 Standard Specifications Memo Summary of Revisions for 2021 Standard Specifications 2021 Standard Specifications for Road and Bridge Construction 2021 Supplemental Specifications 100 SS (Rev. 12-29-25) 200 SS (Rev. 12-29-25) 300 SS (Rev. 08-28-24) 400 SS (Rev. 12-29-25) 500 SS (Rev. 12-27-23) 600 SS (Rev. 12-29-25) 700 SS (Rev. 12-29-25) 900 SS (Rev. 12-29-25)