Road traffic control device

Traffic Control Devices are markers, signs and signal devices used to inform, guide and control the traffic and the pedestrians. These devices are usually placed adjacent, over and/or along the highways, roads, traffic facilities and other public areas that require traffic control.

The most popular traffic control devices are the traffic signs and traffic lights. This is because you can see these devices on the street everyday. However, there are other Traffic Control Devices out there.

Types of Traffic Control Devices

1. Traffic signs are traffic control devices which relay a particular and/or general messages by means of symbols and/or words which follow the general rules set by the Manual on Uniform Traffic Control Devices (MUTCD). Traffic signs also follow standard size, color, design and materials used. These devices are made with reflective materials that illuminates when hit by lights. This is to achieve maximum visibility especially at night.

• Regulatory Signs are traffic signs that are used to convey traffic rules and regulations such as weight limit, speed limit, one way, no parking, stop and others. These signs are generally rectangular in shape and uses white, black and red as its main colors.

• Warning Signs are temporary traffic signs that are used to warn pedestrians and drivers about a potential danger. These signs are usually diamond in shape and uses orange and black as its main colors. Examples of warning signs are advisory speed plate, road closed sign, flagger signs, workers sign, road machinery sign, blasting zone, turn off gadget warning and others.

• Guide Signs are use for temporary route changes. These signs are generally rectangular in shape and uses black and orange as its primary colors. Examples of guide signs are detour markers, length of work signs, end road work signs and pilot car signs.

2. Portable Changeable Message Signs or PCMS are trafic control devices which can exhibit different traffic messages according to the needs of a specific road. These devices are usually placed on urban freeways which have traffic routing problems. PCMS have a message sign panel, power source, control system, transporting equipment and mounting. These devices also follow a uniform shape, design and color that were set by the MUTCD.

3. High Level Warning Devices are traffic control devices that are usually placed on high level areas, such as but not limited to vehicle top, street poles and other places not lower than 8 feet. These devices are also called as flag tree simply because it features two square flags that has high intensity colors such as orange and a flashing warning light. This type of traffic control devices are usually placed on high traffic density urban areas.

4. Chanelling Devices are basically used to warn drivers and pedestrians and to redirect them to a safer route. This type of traffic control device are usually placed several meters away from areas where there are possible dangers such as road construction, dangerous street curvature, severely cluttered environment and unsafe road conditions.

• Cones are chanelling devices made with vehicle-friendly but durable materials that are predominantly bright in color, not less than 18 inches in height and are shape like a cone, thus its name. These are used to confine a particular area or divide traffic lanes temporarily.

• Tubular Markers on the other hand are chanelling devices that are cylindrical in shape and features a reflective design. It stands not less than 18 inches in height and has a body diameter of 2 inches. Tubular markers are usually made with premium grade steel and features a heavy base structure. It works the same way as a cone.

• Vertical Panels are reflective traffic control devices which measure at lease 8 inches wide and 24 inches high. These are predominantly bright orange in color with white stripe details. These panels are used to redirect foot and/or vehicle traffic. It works as a perfect barricade replacement in places that has limited spaces.

• Drums are big chanelling devices that are used to restrict a highly dangerous. These device are made with industrial grade materials that are painted with highly reflective orange coating with white stripe details.. These drums are usually filled with sands and water for added stability.

• Barricades are chanelling devices used to redirect traffic on high-speed roads and expressways. There are different types of barricades depending on its size, design and applications. Barricades may be a fixed or portable traffic control device.

• Temporary Raised Island are pavements that are usually 4 inches in height and 18 inches wide that are used for temporary traffic control applications. This traffic control device follow the standard design set by the AASHTO Roadside Design Guide.

• Portable Barriers are commonly used on industrial and commercial applications. These are used to protect and guide foot and vehicle traffic. Portable barriers are tubular n shape ad has a chain or belt attachment.

5. Markings are traffic control devices that are used to guide vehicle and foot traffic. These devices are used to temporarily or permanently divide a certain area into two or more traffic lanes.

• Pavement Markings are traffic control devices that are painted directly on pavements, roads and highways. These are usually permanent markings that are used to lead drivers and pedestrians to a certain area. Preformed reflective tapes can also be used as pavement markings for temporary intents.

• Interim Markings are temporary markings used in place of a pavement for two weeks or until a real pavement is installed in that specific area. These broken-line markings are at lease 4 feet long.

• Raised Pavement Markings are used in temporary roadways, detours and other lane alignment changes. There are reflective and non-reflective raised pavement marking and these marking can stand both dry and wet weather.

• Delineators, unlike the other markings are tubular metal traffic control devices used to outline roadways and paths. These are about 4 feet high and are painted either yellow or white or combination.

6. Lighting Devices are traffic control devices that are used to warn and guide drivers and pedestrians. These devices are usually attached to other traffic control devices cuh as barriers, barricades, tubular markers and drums and works as an added warning device to avoid unwanted accidents.

• Traffic lights are traffic control devices used for a smooth traffic shifting whenever there is a road intersection. Traffic lights feature four different lights that conveys different meanings. The red flashing light means that the vehicle facing the traffic light must come to a complete stop. The yellow flashing light means that the vehicles facing the traffic light must slow down and prepare for a close full stop. The green flashing light means that the vehicle facing the traffic light can proceed when it is safe to do so. The flashing arrow means that the vehicle moving in the same direction that the arrow is pointing to can proceed whenever the way is clear.

• Flood Lights are used for temporary applications. These devices are set on urban freeways sespecially at night. This provides additional lightning to enhance visibility on the road.

• Flashing Identification Beacons or flashing electric lights work as additional warning devices. These are usually mounted to other traffic control devices. It takes some time to install these lights and since these are battery powered, when set, these devices can work 24 hours a day.

• Steady Burning Electric Lamps work similarly to flashing electric light except that its yellow lights are not flashing. These are commonly used for on-road maintenance work.

• Warning Lights are portable, battery-powered lighting devices that can worked as flashing or steady burning lights. These devices can be mounted on other traffic control devices. This device follow the standards set by the ITE Purchase Specification for Flashing and Steady-Burn Warning Lights.

7. Other Traffic Control Devices

• Impact Attenuators are traffic control devices used to protect vehicles and pedestrian from the ends of other traffic control devices such as barriers, cones and hazards. These devices are used to make sure that vehicles and pedestrians are properly and safely redirected specially under low-lights. There are two types of impact attenuators: the roadside attenuators and the truck mounted attenuators.

• Temporary Traffic Signals are used for temporary applications such as emergency road maintenance or when a car broke down on road abruptly.

• Rumble Strips are used to warn drivers about an unexpected traffic condition ahead. These strips feature rough-surface that are either embossed or recessed. These strips can be rectangular, circular and/or geometrical in shape and are usually place 250 meters ahead of the actual traffic condition.

• Screens are used to completely separate a certain area and to block the drivers' and/or pedestrian's view of the activities happening on the said area. This is to avoid distraction and unwanted accidents. Screens are usually set whenever there are construction long the road or roadside.

• Opposing Traffic Lane Dividers are used to separate two opposing traffic lanes. These devices are placed right in the center part of the road or paths.

Distributors and Manufacturers

Bahrns Material Handling Equipment

US Barricades

Eagle LLC

References

US Occupational Safety and Health Administration

South Dakota Department of Transportation

AASHTO Subcommittee on Traffic Engineering

Ministry of Transport Land Transport Rules

US Department of Transportation MUTCD

Traffic Safety in Alberta