ATSSA Traffic Control Supervisor Re-
certification questions with correct answers
L=(WS²)/60 for 40MPH or less,
L=WS for 45MPH or more - Answer Formula for Min. taper length
The off peak 85th percentile. Which is the speed at or below which 85% of vehicles travel operating speed in free flow conditions - Answer speed used in formulas should be
125' - Answer Distance of L for 25 MPH with 12' Lane width
245' - Answer Distance of L for 35 MPH with 12' Lane width
540' - Answer Distance of L for 45 MPH with 12' Lane width
660' - Answer Distance of L for 55 MPH with 12' Lane width
780' - Answer Distance of L for 65 MPH 12' Lane width
L Minimum - Answer Merging Taper Length
1/2 L Minimum - Answer Shifting Taper Length
1/3 L Minimum - Answer Shoulder Taper Length
50'-100' regardless of speed 6 devices 10'-20' apart - Answer One-Lane, Two-Way Taper (Flagger taper) Length and number of devices
50'-100' per lane - Answer Downstream taper Length
2L - Answer Tangent distance (between tapers)
1/2L - Answer Tangent distance before shifting taper
Buffer Space
Work Space
Traffic Space - Answer Activity Area Sub-components (3)
Recovery Area for errant vehicles: Forgiving design
Protects workers and Motorists
Always completely empty or clear
No vehicles, truck-mounted attenuator, equipment, or materials
STRONGLY RECOMMENDED: unless there is a documented reason not to - Answer Longitudinal Buffer Space
Where road users are returned to their normal path
extends from the downstream end of the work area to the last device such as end work zone sign
May contain:
end work zone sign: usually 500' past last device
downstream taper = 50'-100' per lane - Answer Termination Area is:
certification questions with correct answers
L=(WS²)/60 for 40MPH or less,
L=WS for 45MPH or more - Answer Formula for Min. taper length
The off peak 85th percentile. Which is the speed at or below which 85% of vehicles travel operating speed in free flow conditions - Answer speed used in formulas should be
125' - Answer Distance of L for 25 MPH with 12' Lane width
245' - Answer Distance of L for 35 MPH with 12' Lane width
540' - Answer Distance of L for 45 MPH with 12' Lane width
660' - Answer Distance of L for 55 MPH with 12' Lane width
780' - Answer Distance of L for 65 MPH 12' Lane width
L Minimum - Answer Merging Taper Length
1/2 L Minimum - Answer Shifting Taper Length
1/3 L Minimum - Answer Shoulder Taper Length
50'-100' regardless of speed 6 devices 10'-20' apart - Answer One-Lane, Two-Way Taper (Flagger taper) Length and number of devices
50'-100' per lane - Answer Downstream taper Length
2L - Answer Tangent distance (between tapers)
1/2L - Answer Tangent distance before shifting taper
Buffer Space
Work Space
Traffic Space - Answer Activity Area Sub-components (3)
Recovery Area for errant vehicles: Forgiving design
Protects workers and Motorists
Always completely empty or clear
No vehicles, truck-mounted attenuator, equipment, or materials
STRONGLY RECOMMENDED: unless there is a documented reason not to - Answer Longitudinal Buffer Space
Where road users are returned to their normal path
extends from the downstream end of the work area to the last device such as end work zone sign
May contain:
end work zone sign: usually 500' past last device
downstream taper = 50'-100' per lane - Answer Termination Area is:
