The 2004 Standard Highway Signs Book published by the FHWA included the addition of interstate shields in the form of pavement markings. Since that time, there has been a growing use of these “horizontal surface signs” in lieu of or as a supplement to the typical shoulder-mounted or overhead traffic signs. The SHS Book illustrates three sizes including 6’ x 15’, 7’ x 17’6”, and 8’ x 20’, all of which are available using PREMARK® preformed thermoplastic with VIZIGRIP® retroreflective glass beads.
ENNIS-FLINT® by PPG PREMARK® Preformed Thermoplastic Shields
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Depending on the particular location and need, other sizes can be made. Interstate shields as large as 8’ x 36’ are very effective on highways with higher speed limits. PreMark preformed thermoplastic interstate shields also include ViziGrip retroreflective glass beads due to the larger dimensions of the symbols and for the added safety benefit that the ViziGrip retroreflective glass beads provide to motorcyclists by adding grip to the pavement marking. PreMark preformed thermoplastic is applied using the Flint 2000EX or Magnum Heat Torch.