MOT Temporary Traffic Control Plans 3 — Questions and Answers
Question 1: Under the MUTCD, what is the minimum retroreflectivity requirement for temporary traffic control signs used in work zones?
- They must be fluorescent yellow-green only
- They must meet the same retroreflectivity standards as permanent signs (Correct answer)
- They have no retroreflectivity requirement if used during daytime only
- They must use Diamond Grade sheeting exclusively
Correct answer: They must meet the same retroreflectivity standards as permanent signs
MUTCD requires TTC signs to meet the same minimum retroreflectivity levels as permanent regulatory and warning signs.
Question 2: A TTC plan specifies 'channelizing devices at 20-foot spacing.' Under what condition would spacing need to be reduced?
- When the posted speed limit is above 45 mph
- Through a curved or complex transition area where visual guidance is critical (Correct answer)
- When the work zone is longer than one mile
- When the contractor has extra devices available
Correct answer: Through a curved or complex transition area where visual guidance is critical
Tighter device spacing is required in curved or complex areas to provide continuous clear guidance to drivers through the transition.
Question 3: What is the significance of a 'short-duration' work zone classification in TTC plan development?
- It requires a full engineering study before setup
- It allows simplified TTC setups because the operation lasts 15 minutes to 1 hour (Correct answer)
- It exempts the contractor from using any channelizing devices
- It mandates police presence at all times
Correct answer: It allows simplified TTC setups because the operation lasts 15 minutes to 1 hour
Short-duration operations (15 min to 1 hr) permit simplified TTC arrangements compared to longer-term stationary work zones.
Question 4: In a TTC plan for a divided highway, what must be included when closing a median crossover for emergency access?
- A Type III barricade and a flagger on each side
- Alternative emergency vehicle access routes clearly shown on the plan (Correct answer)
- A 24-hour police detail at the crossover
- A detour sign redirecting all traffic to the nearest interchange
Correct answer: Alternative emergency vehicle access routes clearly shown on the plan
TTC plans must document and provide alternative emergency vehicle access whenever a median crossover is closed.
Question 5: A contractor wants to use arrow boards at a lane closure. According to MUTCD, which mode should the arrow board display for a lane closure taper?
- Flashing caution mode
- Sequential chevron mode (Correct answer)
- Flashing dot mode
- Steady burn mode
Correct answer: Sequential chevron mode
Sequential chevron (arrow) mode is the correct display for an arrow board at a lane closure taper to direct traffic to merge.
Question 6: Which document typically serves as the standard detail sheet for common TTC setups so contractors don't need a custom engineered plan for routine closures?
- The project SWPPP
- Standard Highway Plans or DOT Standard TTC Details (Correct answer)
- The contractor's safety manual
- OSHA 29 CFR 1926 Subpart Q
Correct answer: Standard Highway Plans or DOT Standard TTC Details
State DOT Standard TTC Details (Standard Highway Plans) provide pre-approved layouts for routine work zone scenarios.
Question 7: When a TTC plan is revised during the project due to changed field conditions, what must occur before implementing the revised plan?
- The contractor must notify OSHA 48 hours in advance
- The revision must receive approval from the agency engineer or authorized representative (Correct answer)
- All workers must complete additional training
- A new environmental permit must be obtained
Correct answer: The revision must receive approval from the agency engineer or authorized representative
Any revisions to an approved TTC plan must be reviewed and approved by the agency engineer before implementation.
MOT Temporary Traffic Control Plans 3
Under the MUTCD, what is the minimum retroreflectivity requirement for temporary traffic control signs used in work zones?