Lesson 3: The Work Zone

Aim: After completing this lesson you will be able to name and describe the primary parts of the work zone.

Your exposure to being hit is the greatest when you are placing or removing traffic control devices in the work zone, so be alert. When setting up the work zone, make sure that all signs and devices are in place before you start any work. First, put up the advance signs in both directions, then position the flagger if there will be one, then complete the transition and work zone channelization areas. Move with the traffic whenever possible, except when closing down the work zone. Pick your traffic controls up in reverse order, starting with the End Road Work sign and working towards the Road Work Ahead sign.

The work zone typically consists of 5 parts:

Diagram showing the 5 parts of a workzone

1. Advanced Warning Area

The Advance Warning Area should use three types of signs:

At higher speeds, space the signs 500 feet apart

At lower speeds, space the signs at least 100-350 feet apart

Locations of signs, flaggers, and tapers should be adjusted for field conditions that make them hard to see, such as trees, curves or hills.

 

Road Type Distance Between Signs
Rural 500 feet
Urban ≥45 mph 350 feet
Urban 35-40 mph 200 feet
Urban ≤30 mph 100 feet
Freeway/Expressway See MUTCD

 

2. Transition Area

Narrow pavement, reduction of travel lanes, or a lane closure may require moving traffic out of its normal path. The transition area is where the change in traffic flow occurs, often using cones or barrels. The area where the actual shift is made is called the taper. The length of the taper depends on the approach speed and the width of the shift.

The transition area should:

3. Buffer Area

The unoccupied space between the transition area and the work area is the buffer area. This area should be free of all equipment, vehicles, and construction materials. It provides room to stop for drivers who do not see or who do not follow signs or flagger guidance. The length of this area varies depending on traffic speed, volume, and conditions.

 

85th Percentile approach speed (mph) Buffer space length (feet)
20 115
25 155
30 200
35 250
40 305
45 360
50 425
55 495
60 570
65 645

 

The buffer area is:

4. Work Area

The work area is where workers and equipment are located. Channelizing devices are used throughout the area to keep traffic in the non-work lane.

Some work zone area safety suggestions are:

5. Termination Area

This area advises drivers that they are past the work site and may resume normal driving. It is good practice to put an END ROAD WORK sign here. A short down stream taper is also recommended. Five cones in 100 feet is fine.

The termination area:

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