Your Guide To Automated Flagger Assistance Devices (AFADs)

Flaggers put their lives in danger each time they enter a work zone. With automated flagger assistance devices (AFADs), personnel can distance themselves from traffic and stay safe. We’ve provided concise introductory information about AFADs and how to implement them in traffic management. This guide will answer your questions about AFADs and help you decide whether to integrate this type of system into your project’s traffic control methods. 

What Is An Automated Flagger Assistance Device?

AFADs direct traffic temporarily and are often set up during pavement patching, bridge work, and guardrail repairs. AFADs are used when there is only one lane of oncoming traffic in the direction that needs to be controlled. Personnel operate AFADs remotely and are thus removed from the throes of traffic. Certified flaggers can operate AFADs from a safer space like behind a barrier or inside a nearby vehicle. 

History of Automated Flagger Assistance Devices

In the 1990s, AFADs hit the market in North America. They were tested by various state and province highway departments in the United States and Canada. After several years, the U.S. federal government approved the use of AFADs. Shortly after, the U.S. Department of Transportation updated the Manual on Uniform Traffic Control Devices (MUTCD) to include guidelines for the use of AFADs. 

Types of Automated Flagger Assistance Devices

AFADs signal to drivers when to stop and when to proceed. The U.S. Federal Highway Administration recognizes two types of AFADs, which are described in Section 6E of the MUTCD. Either type of AFAD can be portable or mounted to a trailer or cart. 

  • Stop/Slow Sign: This specific type of traffic flagger has a remote-controlled Stop/Slow sign that directs traffic.
  • Red/Yellow Lens: This specific type of traffic flagger has remote-controlled red and yellow lenses and a gate arm to control traffic.

How to Use Automated Flagger Assistance Devices

Although AFADs are controlled remotely, they must be operated by certified flaggers at all times. The following section explains how to use AFADs in temporary traffic control (TTC) zones. 

Traffic Control 

AFADs can be used within TTC zones in these ways:

  • You can place one AFAD at each end of the TTC zone. One flagger controls one AFAD. Another flagger controls the other AFAD.
  • You can have one AFAD at one end of a TTC zone with a flagger at the other end. Only do this if the flagger can monitor both the AFAD and approaching traffic. 
  • The same flagger can control two AFADs if the flagger has a clear view of both devices and approaching lanes of traffic. 

Placement on the Road

AFADs should be set up on the shoulder of the road. However, they may be placed within the lane to be more visible to motorists. If the AFAD has a gate arm, the extended arm cannot enter the adjacent lane. 

State guidelines may affect how far two AFADs can be placed from one another. For many states, the maximum distance between AFADs ranges from 800 and 1,000 feet; however, some states may allow a distance of up to 1 to 2 miles depending on the number of flagging personnel at the site. For example, AFADs can be placed up to a mile apart in New Hampshire. Check with your state’s standards to see if there are any special requirements or restrictions on how you can use AFADs in your area.

Limitations to Automated Flagger Assistance Devices

There are limits to how you can integrate AFADs into road construction projects. Since AFADs are not a permanent tool for directing traffic, their special purpose applies only to temporary traffic control situations. Under most circumstances, AFADs are acceptable for use in work zones as long as they are controlled by a certified flagger and visible to oncoming motorists. 

Type of Traffic Control 

AFADs can be used on two-lane highways when one lane of traffic opposes the other. 

In this scenario, one AFAD should be placed on either side of the TTC zone so that one AFAD controls traffic from entering from one direction and the other AFAD controls traffic entering from the opposite direction. 

Typically, AFADs are used for lane closures during small construction projects like pavement patching or bridge maintenance. Just remember, one AFAD cannot control multiple lanes of traffic. Each automated flagging device can only direct one lane of approaching traffic for a short period of time. 

Average Traffic Counts

AFADs can be used in a variety of traffic levels. Some states may have regulations on when and where you can use AFADs based on average daily traffic counts. The state of Virginia allows AFAD use on roads with an average daily traffic count of 12,000 vehicles or less. Yet in Minnesota, AFADs are only used on roads with an average daily traffic count of up to 1,500. Be sure to check your state’s traffic limitations before using an AFAD for your next road project. 

Time of Day

You can use AFADs during the day and at night. If you plan to use an AFAD at night, it must be illuminated so that motorists can see the automated flagger signals and messages from a distance. 


AFADs require a certified flagger to operate them. Flaggers should never leave this specialized equipment unattended while in use. Certified flaggers onsite can provide maintenance to the device if it stops working correctly. Preventive maintenance is also essential for traffic management equipment. If the AFAD were to malfunction, flaggers would need to direct traffic manually, which is a system that requires the help of more workers and is more dangerous.

Benefits to Road Workers & Users

While AFADs do require more setup than traditional flagging, they present several advantages for road workers. The first and most important of these benefits is better safety. With AFADs, flaggers stand apart from approaching traffic and minimize their risk of injury from passing vehicles. 

Surveys from state transportation departments show that both road workers and drivers have positive reactions to AFADs. For example, the Missouri Department of Transportation found that highway workers thought AFADs were “easy to set up” and safer than traditional flagging. In another report, Ohio personnel felt safer with AFADs onsite. These workers observed that using AFADs increased their productivity, as fewer crew members were required to operate the devices. 

AFADs are simple for personnel to operate from a distance, and they are more visible than human flaggers. During a test by Minnesota’s Department of Transportation, researchers compared traditional flagging methods with AFADs. At the sites with AFADs, drivers were able to follow the directions given by the devices, and there were no work zone intrusions reported. In another study, the Washington State Department of Transportation observed that most drivers found AFADs easy to understand. 

Every work zone is different. Depending on factors, such as the location and type of project, you can use AFADs to effectively control traffic and minimize work zone intrusions. AFADs can make your work zone safer for everyone involved. They protect human flaggers from the direct line of traffic and help drivers better understand how to travel through the work zone. 

Traffic flagging companies IntelliStrobe provides industry-leading Red/Yellow AFADs. Contact us today to learn more about how our AFADs can make your work zone a safer place. 

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