ATSSA TRAFFIC CONTROL SUPERVISOR FINAL PAPER 2025/2026
QUESTIONS WITH ANSWERS GRADED A+
✔✔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 -
✔✔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 - ✔✔Termination Area is:
can contain: (2)
✔✔100' - ✔✔Recommended Advanced Warning Sign Spaceing: Urban (low speed)
✔✔350' - ✔✔Recommended Advanced Warning Sign Spaceing: urban (high speed)
✔✔500' - ✔✔Recommended Advanced Warning Sign Spaceing: Rural
✔✔1000', 1500', and 2640' - ✔✔Recommended Advanced Warning Sign Spaceing:
freeways and expressways (3)
✔✔1 Mile
50%
shoulder at beginning of taper if possible, if not, as close to beginning as possible inside
taper. - ✔✔Arrow board visibility distance by design:
night time dimming:
location:
✔✔taper: not to exceed distance in feet = to posted speed limit
tangent: distance = double posted speed limit - ✔✔device spacing taper:
tangent:
✔✔A: Low intensity flashing
B: High-intensity flashing
C: Steady Burn
D: 360° steady burn - ✔✔Warning lights types:
Type A:
Type B:
, Type C:
Type D:
✔✔Uses for portable changeable message sign PCMS - ✔✔speed drops
significant delays
adverse conditions
advance notice of closures
advance notice of road changes
reinforce static signage
updated guidance information
placed 500'-800' ahead of workzone conflicts or 1.5-2 miles ahead of complex traffic
control
✔✔What was observed (devices and position, weather, traffic flow, flagging
opperations, incidents)
needed corrections and if corrected, when? - ✔✔What to doccument
✔✔
L=(WS²)/60 for 40MPH or less,
L=WS for 45MPH or more - ✔✔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 - ✔✔speed used in formulas should be
✔✔125' - ✔✔Distance of L for 25 MPH with 12' Lane width
✔✔245' - ✔✔Distance of L for 35 MPH with 12' Lane width
✔✔540' - ✔✔Distance of L for 45 MPH with 12' Lane width
✔✔660' - ✔✔Distance of L for 55 MPH with 12' Lane width
✔✔780' - ✔✔Distance of L for 65 MPH 12' Lane width
✔✔L Minimum - ✔✔Merging Taper Length
✔✔1/2 L Minimum - ✔✔Shifting Taper Length
✔✔1/3 L Minimum - ✔✔Shoulder Taper Length
✔✔50'-100' regardless of speed
6 devices 10'-20' apart - ✔✔One-Lane, Two-Way Taper (Flagger taper) Length and
number of devices
QUESTIONS WITH ANSWERS GRADED A+
✔✔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 -
✔✔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 - ✔✔Termination Area is:
can contain: (2)
✔✔100' - ✔✔Recommended Advanced Warning Sign Spaceing: Urban (low speed)
✔✔350' - ✔✔Recommended Advanced Warning Sign Spaceing: urban (high speed)
✔✔500' - ✔✔Recommended Advanced Warning Sign Spaceing: Rural
✔✔1000', 1500', and 2640' - ✔✔Recommended Advanced Warning Sign Spaceing:
freeways and expressways (3)
✔✔1 Mile
50%
shoulder at beginning of taper if possible, if not, as close to beginning as possible inside
taper. - ✔✔Arrow board visibility distance by design:
night time dimming:
location:
✔✔taper: not to exceed distance in feet = to posted speed limit
tangent: distance = double posted speed limit - ✔✔device spacing taper:
tangent:
✔✔A: Low intensity flashing
B: High-intensity flashing
C: Steady Burn
D: 360° steady burn - ✔✔Warning lights types:
Type A:
Type B:
, Type C:
Type D:
✔✔Uses for portable changeable message sign PCMS - ✔✔speed drops
significant delays
adverse conditions
advance notice of closures
advance notice of road changes
reinforce static signage
updated guidance information
placed 500'-800' ahead of workzone conflicts or 1.5-2 miles ahead of complex traffic
control
✔✔What was observed (devices and position, weather, traffic flow, flagging
opperations, incidents)
needed corrections and if corrected, when? - ✔✔What to doccument
✔✔
L=(WS²)/60 for 40MPH or less,
L=WS for 45MPH or more - ✔✔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 - ✔✔speed used in formulas should be
✔✔125' - ✔✔Distance of L for 25 MPH with 12' Lane width
✔✔245' - ✔✔Distance of L for 35 MPH with 12' Lane width
✔✔540' - ✔✔Distance of L for 45 MPH with 12' Lane width
✔✔660' - ✔✔Distance of L for 55 MPH with 12' Lane width
✔✔780' - ✔✔Distance of L for 65 MPH 12' Lane width
✔✔L Minimum - ✔✔Merging Taper Length
✔✔1/2 L Minimum - ✔✔Shifting Taper Length
✔✔1/3 L Minimum - ✔✔Shoulder Taper Length
✔✔50'-100' regardless of speed
6 devices 10'-20' apart - ✔✔One-Lane, Two-Way Taper (Flagger taper) Length and
number of devices
