CTQP Roadway Traffic Control Inspection 4 — Questions and Answers
Question 1: When a flagging operation is required at night, what additional safety measure must flaggers use beyond standard daytime requirements?
- Use only red flags instead of paddles
- Wear Class 3 high-visibility garments and use illuminated wands or flashlights (Correct answer)
- Station themselves at least 1,000 feet from the work zone
- Require a minimum of three flaggers per lane
Correct answer: Wear Class 3 high-visibility garments and use illuminated wands or flashlights
Nighttime flagging requires Class 3 high-visibility garments and illuminated signaling devices so motorists can clearly see flaggers in low-light conditions.
Question 2: According to MUTCD standards, what is the minimum height for temporary traffic control signs mounted on portable sign supports?
- 1 foot above the ground
- 2 feet above the nearest travel lane
- At least 1 foot clearance from pavement surface, typically 7 feet for pedestrian areas (Correct answer)
- 5 feet measured to the top of the sign
Correct answer: At least 1 foot clearance from pavement surface, typically 7 feet for pedestrian areas
MUTCD requires at least 1 foot clearance from pavement for roadside signs, but 7 feet clearance where pedestrians may pass beneath the sign.
Question 3: A temporary lane closure requires which of the following taper configurations at the upstream end?
- A straight merge line painted on the pavement
- A merging taper using channelizing devices to guide traffic out of the closed lane (Correct answer)
- A termination taper placed before the work area
- A downstream taper set at the beginning of the activity area
Correct answer: A merging taper using channelizing devices to guide traffic out of the closed lane
A merging taper at the upstream end uses channelizing devices in a diagonal pattern to guide vehicles from the closed lane into the open lane.
Question 4: Which condition would require an inspector to immediately stop work and notify the engineer regarding a TTC plan?
- A single cone is displaced more than 2 feet from its intended location
- Flaggers are wearing Class 2 vests in a low-speed urban zone
- Workers are operating within the buffer space without authorization or the TTC plan is not on-site (Correct answer)
- One advance warning sign is missing its orange border stripe
Correct answer: Workers are operating within the buffer space without authorization or the TTC plan is not on-site
Workers inside the buffer space without authorization or the absence of the TTC plan on-site are critical safety violations requiring immediate work stoppage.
Question 5: When inspecting temporary pavement markings, what characteristic must yellow centerline markings on a two-lane two-way road have?
- They must be white and retroreflective
- They must be yellow, retroreflective, and placed to match the geometric alignment of permanent markings (Correct answer)
- They may be any color as long as they are retroreflective
- They must be double solid lines only, never dashed
Correct answer: They must be yellow, retroreflective, and placed to match the geometric alignment of permanent markings
Temporary centerline markings on two-lane two-way roads must be yellow and retroreflective, following the same alignment rules as permanent markings.
Question 6: What is the primary purpose of the downstream taper in a temporary traffic control zone?
- To alert drivers of the upcoming work zone ahead
- To allow traffic to return to its normal path after passing the work area (Correct answer)
- To separate opposing traffic flows through the work zone
- To designate the beginning of the activity area
Correct answer: To allow traffic to return to its normal path after passing the work area
The downstream taper guides traffic back to the normal travel path after it has passed the activity area of the work zone.
Question 7: During a TTC inspection, the inspector notices a Type III barricade being used as a channelizing device in the taper. Is this acceptable?
- Yes, Type III barricades can substitute for cones or drums anywhere in the TTC zone
- No, Type III barricades are only appropriate for road closures, not lane-shift tapers where cones or drums are required (Correct answer)
- Yes, as long as the barricade has retroreflective sheeting on both rails
- No, barricades are prohibited from all temporary traffic control applications under MUTCD
Correct answer: No, Type III barricades are only appropriate for road closures, not lane-shift tapers where cones or drums are required
Type III barricades are designated for road closures; lane-shift or merging tapers require channelizing devices such as cones, tubular markers, or drums.
CTQP Roadway Traffic Control Inspection 4
When a flagging operation is required at night, what additional safety measure must flaggers use beyond standard daytime requirements?