ATSSA TRAFFIC CONTROL SUPERVISOR RE-
CERTIFICATION (MISSING SOME BASICS)
QUESTIONS AND ANSWERS WITH SOLUTIONS 2026
Formula for Min. taper length - correct answer-L=(WS²)/60 for 40MPH or less,
L=WS for 45MPH or more
speed used in formulas should be - correct answer-
The off peak 85th percentile. Which is the speed at or below which 85% of vehicles travel operating sp
eed in free flow conditions
Distance of L for 25 MPH with 12' Lane width - correct answer-125'
Distance of L for 35 MPH with 12' Lane width - correct answer-245'
Distance of L for 45 MPH with 12' Lane width - correct answer-540'
Distance of L for 55 MPH with 12' Lane width - correct answer-660'
Distance of L for 65 MPH 12' Lane width - correct answer-780'
Merging Taper Length - correct answer-L Minimum
Shifting Taper Length - correct answer-1/2 L Minimum
Shoulder Taper Length - correct answer-1/3 L Minimum
One-Lane, Two-Way Taper (Flagger taper) Length and number of devices - correct answer-50'-
100' regardless of speed
6 devices 10'-20' apart
, Downstream taper Length - correct answer-50'-100' per lane
Tangent distance (between tapers) - correct answer-2L
Tangent distance before shifting taper - correct answer-1/2L
Activity Area Sub-components (3) - correct answer-Buffer Space
Work Space
Traffic Space
Longitudinal Buffer Space - correct 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) - correct 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) - correct answer-100'
Recommended Advanced Warning Sign Spaceing: urban (high speed) - correct answer-350'
Recommended Advanced Warning Sign Spaceing: Rural - correct answer-500'
CERTIFICATION (MISSING SOME BASICS)
QUESTIONS AND ANSWERS WITH SOLUTIONS 2026
Formula for Min. taper length - correct answer-L=(WS²)/60 for 40MPH or less,
L=WS for 45MPH or more
speed used in formulas should be - correct answer-
The off peak 85th percentile. Which is the speed at or below which 85% of vehicles travel operating sp
eed in free flow conditions
Distance of L for 25 MPH with 12' Lane width - correct answer-125'
Distance of L for 35 MPH with 12' Lane width - correct answer-245'
Distance of L for 45 MPH with 12' Lane width - correct answer-540'
Distance of L for 55 MPH with 12' Lane width - correct answer-660'
Distance of L for 65 MPH 12' Lane width - correct answer-780'
Merging Taper Length - correct answer-L Minimum
Shifting Taper Length - correct answer-1/2 L Minimum
Shoulder Taper Length - correct answer-1/3 L Minimum
One-Lane, Two-Way Taper (Flagger taper) Length and number of devices - correct answer-50'-
100' regardless of speed
6 devices 10'-20' apart
, Downstream taper Length - correct answer-50'-100' per lane
Tangent distance (between tapers) - correct answer-2L
Tangent distance before shifting taper - correct answer-1/2L
Activity Area Sub-components (3) - correct answer-Buffer Space
Work Space
Traffic Space
Longitudinal Buffer Space - correct 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) - correct 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) - correct answer-100'
Recommended Advanced Warning Sign Spaceing: urban (high speed) - correct answer-350'
Recommended Advanced Warning Sign Spaceing: Rural - correct answer-500'
