On average, over 700 fatalities occur in work zones each year. Commercial motor vehicle (CMV) and passenger vehicle drivers both need to be particularly careful while traveling through work zones. Trucks and buses have limited maneuverability and large blind spots, both of which make operating in these areas more challenging for them. In fact, large trucks are disproportionately involved in work zone crashes.
Risks in and Around Work Zones
Workers in highway work zones are most often exposed to risk to injury from the movement of construction vehicles and equipment within and around work zones.
Highway workers routinely work close to construction vehicles and motor vehicle traffic.
Highway workers work in conditions of low lighting, low visibility, and inclement weather, and may work in congested areas with exposure to high traffic volume and speeds.
Vehicle or equipment operators risk injury due to overturn, collision, or being caught in running equipment.
Flaggers and other workers on foot are exposed to the risk of being struck by traffic vehicles or construction equipment most often if they are not visible to motorists or equipment operators.
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1. What is the most common reason flaggers and other workers on foot are injured by vehicles and equipment in work zones?
a. Lack of visibility
b. Excessive speed of vehicles
c. Confusion in directing traffic
d. Non-compliance with warning signs
A traffic control plan helps move motorist traffic safety through or around roadway work zones to protect the public and workers.
The traffic control plan makes use of traffic control devices, standard signage, and buffer and transition zones. When flaggers will
be used on a job lasting more than one day, there must be a current site-specific traffic control plan kept on site. There are two types of traffic control plans: Temporary and Internal. The type of work you're doing will define exactly which type of traffic control plan you need.
Temporary Traffic Control Plans (TTCPs)
Temporary Traffic Control Plans (TTCPs) are designed to assist road users by providing appropriate visual cues and guidance. In the Temporary Traffic Control zone, construction vehicles and equipment moving inside create a risk to workers on foot.
Activity Area. The Temporary Traffic Control activity area is the section of the highway where the work activity takes place. It is comprised of the work space, the traffic space, the buffer space, and the incident management vehicle storage space. Click on the button below to see more information on activity area spaces.
Areas and Spaces (Click to enlarge.)
Spaces within the activity area
Work Space. The work space is that portion of the roadway closed to traffic and set aside for workers, equipment, and material. Work space may be fixed or may move as work progresses. Long-term work spaces are usually delineated by channelizing devices or shielded by barriers to exclude traffic and pedestrians. the Internal Traffic Control Plan covers safety inside the work space.
Traffic Space. The traffic space is the portion of the roadway in which traffic is routed through the activity area.
Buffer Space. The buffer space is an optional feature in the activity area that separates traffic flow from the work activity or a potentially hazardous area and provides recovery space for an errant vehicle.
Incident Management Vehicle Storage Space. When work occurs on a high-volume, highly congested facility in an urban area, it is optional to allow space to store emergency vehicles (e.g., tow trucks) to respond quickly to traffic incidents.
Click on the button below to see actions to take in developing a TTCPs.
Actions to consider when developing and implementing a TTCP.
Restrict personnel access points into work areas and define/designate "no backing zones" and "pedestrian-free zones."
Design into the Temporary Traffic Control Plan flow paths for equipment and vehicle traffic to minimize backing maneuvers where possible. There should also be buffer spaces to protect pedestrian workers from straying traffic vehicles and/or work zone equipment.
Establish procedures for entering and exiting the work zone.
Train all employees on the Temporary Traffic Control Plan and its precautionary measures.
Examples of TTCP strategies to consider for operations:
Reduced shoulder and lane widths to maintain number of lanes
Reduced length of work zone lane closures or impact area, segmenting work zone
Lane closure to provide worker safety, increased lateral buffer
Vehicle restrictions (trucks, oversize, local traffic, etc.)
Emergency vehicle access
Emergency pullouts for disabled vehicles or enforcement
Internal Traffic Control Plans (ITCPs)
In contrast to a TTCP, an internal traffic control plan (ITCP) addresses hazards inside the activity area work space of a temporary traffic control zone. The objective of the ITCP is to provide a safe traffic pattern and access plan for the contractor, equipment and materials, and
improving the overall safety of the work zone. The ITCP is developed by the Contractor prior to beginning work on the project
Click on the button below to see actions to take in developing and implementing ITCPs.
The ITCP should include internal haul routes, work zone access points, and should consider the following:
Reduce equipment back-ups.
Limit contractor access points within the work zone. Attention should be given to ingress and egress locations.
Establish pedestrian and worker free areas where possible.
Establish work zone layouts appropriate for the work type being performed.
Provide signs within the work zone to give guidance to workers, equipment, trucks, and drivers.
Evaluate acceleration / deceleration areas.
Design buffer spaces to protect workers from errant vehicles or equipment.
Establish a maintenance plan for temporary traffic control devices.
Brief truck drivers on access and internal paths to follow within the site.
Review and update the ITCP on a regular basis at project safety meetings throughout the life of the project.
A designated person monitors and corrects non-compliant behavior.
2. Which traffic control plan is designed primarily to protect workers inside the work space of an work zone activity area?
a. A Vehicle Operations Control Plan (VOCP)
b. A Temporary Traffic Control Plan (TTCP)
c. An Internal Traffic Control Plan (ITCP)
d. A Work Zone Control Plan (WZCP)
Flaggers, equipment operators, and other workers-on-foot (refers to any pedestrian worker on the ground in the work zone) are exposed to
several risks, including being hit if they are not visible to vehicle or heavy equipment operators.
Equipment Operator Risk Factors
Workers who operate construction vehicles or motorized equipment have an increased risk of injury due to rollovers,
collisions, and being caught between or struck by operating equipment. Drivers experiencing long delays become impatient and can act
unpredictably increasing worker exposure. Other driver conditions include drivers that are impaired, drowsy, distracted, or aggressive. Active work should not take place with traffic on both sides of the workers, on the same roadbed, unless there is positive protection.
Traffic Control in Work Zones
Flaggers and other workers assigned to traffic control responsibilities in the work zone work very close to motor vehicles and heavy equipment. This is a major reason for an increased risk of workers getting hit or run over. Therefore, they must be trained in traffic control techniques. Examples of conflicts for drivers, workers, and traffic regulators to consider when developing a TTCP include:
Roadway configuration, merging, tapering, and lane drops
Unstable traffic flow
Clear safety zone issues
Emergency vehicle access
Night work visibility
Confusing or conflicting signs, markings, and features.
3. What is a major reason for the increased risk of getting hit or run over in a construction work zone?
a. A lack of work zone signage
b. Workers not wearing reflective clothing
c. Working close to vehicles and equipment
d. Vehicles entering and exiting the activity area
Employers should conduct crew meetings and train all workers on work zone safety. They should discuss important safety topics including: potential hazards, equipment blind spots, and movement precautions in the activity area.
Employers should also have the following to protect workers in a work zone:
a comprehensive site-specific safety program; and
a Temporary Traffic Control Plan (TTCP)in place for the project site.
Click on the button below to see worker best practices in and around the work zone.
Workers should do the following in an around the work zone:
Wear high-visibility safety apparel (vest and head gear).
Be alert for construction vehicles, equipment, and general traffic.
Check surroundings often for hazards.
Know the plan for traffic flow.
Keep a safe distance from traffic.
Communicate with other workers, especially when there are changes in procedures, locations, or traffic flow pattern.
Stay behind the protective barriers.
If you do not have a reason for being there, do not linger or cross into areas around moving equipment.
Use extra precautions and additional safety apparel at night and during poor weather conditions.
Reduce spacing between channelizing devices (discussed in Module 3) at night to compensate for reduced driver visibility.
Ensure the light levels of arrow panels are set at nighttime levels; daytime settings used at night produce blinding light.
Increase the size of traffic control devices, reflective material, and lettering to improve driver recognition at night.
Keep operators who are working near moving equipment in eye contact.
Remember equipment blind spots and limited visual areas.
Keep windows and mirrors clean.
Watch for workers on foot and know where they are located.
Remember equipment blind spots and limited visual areas.
4. What should be done to improve driver recognition of directions when traveling through a work zone at night?
a. Increase the number of entrances/exits to the work zone
b. Increase the light levels of arrow panels
c. Increase the spacing between channelizing devices
d. Increase the size of devices, reflective material, and lettering
Workers in the roadway are also at risk of injury from a variety of general traffic vehicles passing or entering the work zone, such as:
drivers under the influence of alcohol
sleepy or impaired drivers
impatient, upset, or reckless drivers
drivers using cell phones or other inattentive drivers
law enforcement and emergency vehicles
disabled vehicles pulling in and parking
lost drivers looking for directions
The number of work zone and roadway crashes are increasing and the reason is clear: cell phone use is the primary cause of crashes in a large percentage of work zone and roadway incidents.
An 11-person construction crew was paving the northbound side of a 6-lane interstate highway. The far left and middle lanes of the highway were closed to traffic, with two pavers operating simultaneously in staggered positions. Hot asphalt was delivered to the site in tractor-trailers which queued on the left shoulder while waiting to back up to the pavers. A 34-year-old construction laborer was positioned adjacent to the far left lane, approximately 12 feet behind the paver's work area, shoveling old asphalt from around a catch basin. A tractor-trailer pulled away from the paver in the middle lane and began backing. The driver stopped when he heard other workers yelling. Exiting the vehicle, he found the laborer run over by the four left rear wheels. The laborer was pronounced dead at the scene [Massachusetts Department of Public Health].
Flagging should be used only when all other methods of traffic control are inadequate to direct, or control, traffic.
A TCP showing flagger locations, signs and devices is required for any flagging operation no matter the duration.
Minimum standard flagging paddle size allowed is 18 inches. It is recommended that a 24-inch paddle be used to improve visibility.
In a mobile operation when the flagger is moving with the operation, all signs associated with the flagger must be moved ahead whenever work advances to more than 2 miles from the first advance warning signs.
A "Flagger Ahead" sign must be within 1,500 feet of the flagger and the flagger station must be able to be seen from the sign. If terrain does not allow a motorist to see the flagger from the "Flagger Ahead" sign, the distance between the sign and the flagger must be shortened to allow visual contact. The spacing must not be less than the required distance based on the highway speed.
During hours of darkness, flagger stations must be illuminated by using a portable light plant or balloon type lights. The flagger should be visible and discernible as a flagger from a distance of 1,000 feet.
This is better.
Pilot car use is appropriate for long work areas to help maintain traffic speeds and to guide traffic through the work areas. Pilot car operators must be certified flaggers able to trade off duties with other flaggers.
When flagging at intersections, a recommended best practice is to reduce traffic approaching the intersection to a single lane whenever possible. This may require lane closures and restricting access to turn pockets with channelization devices. If signalized, the signal must be either turned off or set to all red "flash" mode. At no time will traffic be flagged with an active signal in full operation.
The placement of a flagger at the center of an intersection to control traffic is not allowed. The only person allowed to legally control traffic from the center of an intersection is a uniformed police officer. No matter who is performing the intersection flagging, the appropriate advance warning signing is required to be in place.
A four-sign sequence should be used for all flagging on roadways with posted speeds of 45 mph or higher. The "one lane road ahead" sign may need to be replaced with a more appropriate sign if flaggers are used for short traffic stops for truck crossing, tree falling, or other work and traffic will not be alternated in a single lane.
6. For what duration must a traffic control plan that includes flagger locations, signs, and devices be implemented for a project?
a. For the entire duration no matter how long
b. For short durations only
c. Only as needed during prior to and after a project
d. For a prolonged duration
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