ASTM F1554 does not have any mention within the specification about metric diameters, dimensions, or options.  Many ASTM fastener specifications have metric options within the specification or even a specific grade for metric.  For instance, ASTM F3125 Grade A325 structural bolts have a metric grade called F3125 Grade A325M that covers metric diameters.  Or ASTM A563 nuts have a metric option called A563M, as do ASTM F436 washers, which is F436M.  Many other ASTM fastener specifications have grades for metric or clauses/options for metric diameters.  However, ASTM F1554 does not have any options or grades for metric diameters, but it also does not specifically prohibit metric or make mention that the specification only covers imperial diameters.

Prior to 2015, ASTM F1554 mentioned metric diameters in dimensional charts to show the rough cross conversion from imperial to metric for every diameter, but this information has now been removed from the specification, and ASTM F1554 now mentions only imperial diameters.  ASTM F1554 is the only ASTM specification for anchor bolts and does not have a metric grade or a direct metric equivalent.  Potentially the specification could be used to manufacture a metric fastener, but functionally ASTM F1554 is intended for imperial diameters.  Few, if any, US anchor bolt manufacturers are tooled up to produce metric diameter threaded fasteners and the availability of metric diameter round bar necessary to manufacture F1554 anchor bolts is uncommon.  Therefore, designers of projects requiring F1554 anchor bolts should specify imperial diameters and/or allow a soft conversion of metric to imperial dimensions on their projects.