The function of channelizing devices is to warn road users of conditions created by work activities in or near the roadway and to guide road users. ... Channelizing devices provide for smooth and gradual vehicular traffic flow from one lane to another, onto a bypass or detour, or into a narrower traveled way. They are also used to channelize vehicular traffic away from the work space, pavement drop-offs, pedestrian or shared-use paths, or opposing directions of vehicular traffic. ... Channelizing devices include cones, tubular markers, vertical panels, drums, barricades, and longitudinal channelizing devices. MUTCD 2009 Edition with May 2012