Sand barrels in work zones

NHDOT requires that the sand barrel system meet NCHRP 350, Test Level 3 (62.1 mph/100km/h). The contractor is required to submit technical data prior to installation. The details address overall length, width, number of barrels, amount of sand in barrels, connection details, etc.. Sand barrels are not acceptable during the winter months unless they are 10 feet away from the traveled way (TW) (measured to the face of the nearest barrel), or specifically approved in writing by the engineer.