FactSheet 

Work Zone Traffic Safety 

Transportation incidents and workers struck by vehicles or mobile equipment 

account for the highest number of fatal work injuries, according to the Bureau of 

Labor Statistics. Workers such as emergency responders, clean-up, utility, demolition, construction, and others in areas where there are moving vehicles and traffic are exposed to being struck-by moving vehicles. Work zones are used to move 

traffic in an approved direction and are typically identified by signs, cones, barrels, and barriers. 

General 

There must be a traffic control plan for the 

movement of vehicles in areas where there 

are also workers conducting other tasks. 

Drivers, workers on foot, and pedestrians 

must be able to see and understand the 

routes they are to follow. The authority in 

charge, Federal, state, or local, will determine 

the configuration of the temporary traffic control zone for motorists and pedestrians. The 

construction project manager will determine 

the internal traffic control plan within the construction/demolition worksite. When there 

are several projects, coordinated vehicle 

routes and communication between contractors will reduce vehicular struck-by incidents. 

Signs 

Standard highway signs for information, 

speed limits, and work zones will assist drivers in identifying, in designated traffic paths, 

such directives as: EVACUATION ROUTE; DO 

NOT ENTER; REDUCED SPEED AHEAD; 

ROAD CLOSED; and NO OUTLET. Using standard highway signs for internal construction 

worksite traffic control will assist workers in 

recognizing the route they are to use at the 

construction site. 

Traffic Control Devices 

Standard traffic control devices, signals, and 

message boards will instruct drivers to follow 

a path away from where work is being done. 

The authority in charge will determine the 

approved traffic control devices such as 

cones, barrels, barricades, and delineator 

posts that will be used as part of the traffic 

control plan. These standard devices should 

also be used inside the work zone. 

Work Zone Protections 

Various styles of concrete, water, sand, collapsible barriers, crash cushions, and truckmounted attenuators are available to limit 

motorist intrusions into the construction 

work zone. 

Flagging 

Flaggers and others providing temporary 

traffic control should wear high visibility 

clothing with a background of fluorescent 

orange-red or yellow-green and retroreflective material of orange, yellow, white, silver, 

or yellow-green. In areas of traffic movement, this personal protective equipment 

will make the worker visible for at least 

1,000 feet, so that the worker can be seen 

from any direction, and make the worker 

stand out from the background. Check the 

label or packaging to ensure that the garments are performance class 2 or 3. 

Drivers should be warned in advance with 

signs that there will be a flagger ahead. 

Flaggers should use STOP/SLOW paddles, 

paddles with lights, or flags (flags should be 

used only in emergencies.) The STOP sign 

should be octagonal with a red background 

and white letters and border. The SLOW 

sign is the same shape, with an orange 

background and black letters and a border. 
Lighting 

Flagger stations should be illuminated. 

Lighting for workers on foot and equipment 

operators is to be at least 5 foot-candles or 

greater. Where available lighting is not sufficient, flares or chemical lighting should be 

used. Glare affecting workers and motorists 

should be controlled or eliminated. 

Training 

Flaggers should be trained/certified and use 

the signaling methods required by the 

authority in charge. Workers on foot, equipment operators, and drivers in internal work 

zones need to know the routes that construction vehicles will use. Equipment operators 

and signal persons need to know the hand 

signals used on the worksite. Operators and 

workers on foot need to know the visibility 

limits and the “blind spots” for each vehicle 

on site. Workers on foot should wear high 

visibility safety garments designated as class 

1, 2, or 3. Workers should be made aware of 

the ways in which shiftwork and nightwork 

may affect their performance. 

Driving 

Seat belts and rollover protection should be 

used on equipment and vehicles as stated by 

the manufacturer. 

This is one in a series of informational fact sheets highlighting OSHA programs, policies or 

standards. It does not impose any new compliance requirements. For a comprehensive list of 

compliance requirements of OSHA standards or regulations, refer to Title 29 of the Code of Federal 

Regulations. This information will be made available to sensory impaired individuals upon request. 

The voice phone is (202) 693-1999; teletypewriter (TTY) number: (877) 889-5627. 

For more complete information: 

U.S. Department of Labor 

www.osha.gov 

(800) 321-OSHA 

DOC 9/2005