AASHTO Journal - INDOT’s ‘Project Greenlight’ Beefs Up Worker Safety

The Indiana Department of Transportation recently launched a new work zone initiative called Project Greenlight; a program to equip highway workers with wearable “Guardian Angel” safety lights with flashing green patterns that increase worker visibility from all directions.

[Above image by INDOT]

INDOT began piloting the green safety lights in fall 2025 within its three “Hoosier Helper” highway safety patrol areas – Northwest Indiana near Gary, IN; the Indianapolis metropolitan area, and in Southeast Indiana – as well as with highway maintenance crews in the Indianapolis Subdistrict and others throughout the state.

Bright green is the most visible color to the human eye and is the most visible from longer distances, the agency noted, with the color green also easily distinguishable from the rest of INDOT’s standard work zone lighting.

When worn with a high visibility vest, the agency said those lights help workers become 89 percent more visible to the traveling public according to a study from Battelle Memorial Institute.

“Studies show drivers are more likely to move over and slow down when they see these green lights in work zones,” said Lyndsay Quist, INDOT commissioner, in a statement. “The safety of our team is always our top priority as they make improvements to Indiana’s infrastructure, and we hope this small tool will have a big impact.”

As the program moves forward, approximately 375 lights will be distributed across the state, starting with the INDOT Northwest District. INDOT highway technicians and Hoosier Helpers will also be encouraged to use the green lights during nighttime operations, as well as during times of inclement weather like fog, rain or snow, when visibility might be lower.

Other state departments of transportation have also deployed a range of different innovations to improve safety for their highway work crews.

For example, several state DOTs are using automated speed cameras in highway work zones across their respective regions to beef up protections for roadway workers and motorists alike – including the New York State Department of Transportation, the Minnesota Department of Transportation, the Colorado Department of Transportation, and the Arkansas Department of Transportation.