ATSSA TRAFFIC CONTROL SUPERVISOR RE-CERTIFICATION 100% VERIFIED
ANSWERS 2025/2026| GRADED A+
Formula for Min. taper length - ANSWER L=(WS²)/60 for 40MPH or less,
L=WS for 45MPH or more
speed used in formulas should be - ANSWER The off peak 85th percentile. Which is the speed at or
below which 85% of vehicles travel operating speed in free flow conditions
Merging Taper Length - ANSWER L Minimum
Shifting Taper Length - ANSWER 1/2 L Minimum
Shoulder Taper Length - ANSWER 1/3 L Minimum
Downstream taper Length - ANSWER 50'-100' per lane
Tangent distance (between tapers) - ANSWER 2L
Tangent distance before shifting taper - ANSWER 1/2L
Distance of L for 25 MPH with 12' Lane width - ANSWER 125'
Distance of L for 35 MPH with 12' Lane width - ANSWER 245'
Distance of L for 45 MPH with 12' Lane width - ANSWER 540'
Distance of L for 55 MPH with 12' Lane width - ANSWER 660'
, Distance of L for 65 MPH 12' Lane width - ANSWER 780'
One-Lane, Two-Way Taper (Flagger taper) Length and number of devices - ANSWER 50'-100' regardless
of speed
6 devices 10'-20' apart
Activity Area Sub-components (3) - ANSWER Buffer Space
Work Space
Traffic Space
Longitudinal Buffer Space - ANSWER 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
Termination Area is:
can contain: (2) - ANSWER 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
Recommended Advanced Warning Sign Spaceing: Urban (low speed) - ANSWER 100'
Recommended Advanced Warning Sign Spaceing: urban (high speed) - ANSWER 350'
ANSWERS 2025/2026| GRADED A+
Formula for Min. taper length - ANSWER L=(WS²)/60 for 40MPH or less,
L=WS for 45MPH or more
speed used in formulas should be - ANSWER The off peak 85th percentile. Which is the speed at or
below which 85% of vehicles travel operating speed in free flow conditions
Merging Taper Length - ANSWER L Minimum
Shifting Taper Length - ANSWER 1/2 L Minimum
Shoulder Taper Length - ANSWER 1/3 L Minimum
Downstream taper Length - ANSWER 50'-100' per lane
Tangent distance (between tapers) - ANSWER 2L
Tangent distance before shifting taper - ANSWER 1/2L
Distance of L for 25 MPH with 12' Lane width - ANSWER 125'
Distance of L for 35 MPH with 12' Lane width - ANSWER 245'
Distance of L for 45 MPH with 12' Lane width - ANSWER 540'
Distance of L for 55 MPH with 12' Lane width - ANSWER 660'
, Distance of L for 65 MPH 12' Lane width - ANSWER 780'
One-Lane, Two-Way Taper (Flagger taper) Length and number of devices - ANSWER 50'-100' regardless
of speed
6 devices 10'-20' apart
Activity Area Sub-components (3) - ANSWER Buffer Space
Work Space
Traffic Space
Longitudinal Buffer Space - ANSWER 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
Termination Area is:
can contain: (2) - ANSWER 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
Recommended Advanced Warning Sign Spaceing: Urban (low speed) - ANSWER 100'
Recommended Advanced Warning Sign Spaceing: urban (high speed) - ANSWER 350'
