Work Zone Mobility and Safety Program
Photo collage: temporary lane closure, road marking installation, cone with mounted warning light, and drum separated work zones.
Office of Operations 21st Century Operations Using 21st Century Technologies

Best Practice


G4-18: Longitudinal Channelizing Devices in Work Zones


Longitudinal Channelizing Device (LCD) units are used to channelize, or delineate safe pathways for, vehicles and pedestrians in the vicinity of work zones. LCDs help address work zone safety by creating a continuous, physical barrier between the work zone and traffic or between vehicular and pedestrian traffic. The use of LCDs is beneficial at major decision points such as lane closures, exit ramps, driveways, and crossovers. These devices may be used instead of a tapered line of cones, drums, or barricades, which are also commonly used to define a travel path. Typical applications of LCDs include defining travel paths for pedestrians and conforming to the Americans with Disabilities Act (ADA) requirements. LCDs are similar in function to barriers that fall within the category of “positive protection,” although positive protection barriers are often better suited to redirecting traffic (as opposed to delineating pathways) than LCDs.


Longitudinal Channelizing Devices (LCD) are lightweight, mobile, difficult to knock down, and highly-visible to motorists.


LCDs help to separate traffic from the work area and can enhance both motorist and construction crew safety. LCDs create a continuous, physical separation between travel lanes or between accessible pedestrian routes and motorized traffic when temporary pedestrian routes are used to facilitate sidewalk closures. Additionally, these devices improve traffic flow by alerting motorists to construction activity ahead and by giving them ample time to react to changes in travel patterns. These devices are used extensively in work zones to warn drivers of work activities on or near the traveled way, to protect workers in the area, and to guide drivers and pedestrians safely through and around the work zone.
These devices provide more path guidance information, especially in continuous line applications, by preventing drivers and pedestrians from going between devices and entering the work zone. LCDs are more resistant to getting knocked over, and thus, may require less maintenance. Their larger size may command more respect from drivers, thereby reinforcing guidance to drivers to avoid encroaching on temporary pedestrian routes. Additional benefits include all weather durability and crush resistance. LCDs are lightweight, deformable devices that are highly visible, have good target value, and can be linked together. Empty barrier sections can be placed by hand without the need for any heavy lifting equipment, thus permitting LCD use where heavy equipment may be impractical or impossible.


These devices are most applicable in long term work zones where cones, drums, and barricades are inappropriate and continuous separation between motorists and pedestrians is needed.


Maryland, Ohio, Virginia


Kayode Adenaiya, Office of Traffic & Safety, Maryland State Highway Administration
Phone: (410) 787-5864

Duane Soisson
Ohio Department of Transportation
Phone: (614) 466-3649
Paul Kelley, Work Zone Safety Coordinator
Virginia Department of Transportation
Phone: (804) 786-8029

Office of Operations