Module 1: Work Zone Traffic Control

Module 1: Work Zone Traffic Control

Overview of Module 1 Underlying principles of work zone traffic control Manual of Uniform Traffic Control Device (MUTCD) Features of work zone traffic control Hazards associated with work zone traffic control Injury prevention techniques Summary

Work Zone Traffic Control Influences drivers perception of risk Provides information on potential hazards Minimizes aggressive behavior Assists in navigation Engineering concerns for work zones Primary focus: Safe and efficient movement of vehicles through work zone Relatively less emphasis on safety of construction workers

Type of Barrier Rigid Barriers Provide separation between Opposing traffic lanes Traffic lanes and work area Cause damage to motorists if struck Concrete barrier separating traffic lanes and work area Concrete barrier separating opposing traffic

Type of Barrier Flexible barriers (channelizing devices) Provide nominal protection for workers Flexible and deformable, do not cause damage if struck Concrete barriers to separate work area Flexible barrier separating traffic lanes and work area Channelizing devices for delineation

Sample Road Projects and Potential Hazards Vehicles parked within work area Passing traffic in close proximity to the on-foot worker with minimal protection from flexible barrier Flashing arrow board is not operating

Components of Temporary Traffic Control Zones Advanced Warning Area Transition Area Activity Area Work space Traffic space Buffer space Termination Area Traffic Space allows tr affic to pass through the activ ity area Bu ffer Space (Lateral) provide s protection from traffic and workers Work Space (Source: MUTCD 2003) Downstr eam Taper Buffer space (longitudinal) Work space is set aside for worker s, equipment, and material storage Buffer Space (longitudinal) pr ovides protection for traffic and workers Termination Area: lets traffic resume normal operations Activity Area: where work takes place Transition Area: moves traffic out of its normal path Work zone Shoulder Taper A dvance Warning Area: tells traffic what to expect ahead

Worker Safety Considerations in Work Zone Traffic Control Modifying traffic control strategies to influence drivers perception of risk Leads to more careful and slower driving Improves safety for the workers Examples: Providing active warning devices Illuminated arrow boards Reliable advisory speed limit Active message with flashers Narrower lane widths Longer and/or wider buffer zones Rigid barriers to separate workers from travel lanes

Positive Guidance Approach May be used to improve safety in work zones Combines highway/traffic engineering features with what rational drivers expect Considers: Various age groups of drivers Complexity of work zone information handling Limited capability of humans for detecting, processing, and remembering information

MUTCD Manual on Uniform Traffic Control Devices Recognized as the national standard Enforcement agencies often adopt it by reference Provides guidance, options and supporting materials To assist professionals in making decisions regarding the use of traffic control on streets and highways

MUTCD- Part 6: Temporary Traffic Control Primary function of temporary traffic control: To provide for reasonably safe and efficient movement of road users through or around temporary traffic control zones while reasonably protecting workers, responders to traffic incidents, and equipment

Temporary Traffic Control Work zones present constantly changing conditions Unexpected by the road user Creates higher degree of vulnerability for workers

Temporary Traffic Control Devices Temporary traffic control (TTC) devices include Signs Signals Markings Other devices Used to regulate, warn, or guide road users

Types of TTC Applications Each TTC zone is different Many variables affect the needs of each zone: Location of work Duration of work Highway type Geometrics Vertical and horizontal alignment, intersections, interchanges, etc. Road user volumes Road vehicle mix (buses, trucks, and cars) and road user speeds

Work Duration Major factor in determining the number and types of devices used in TTC zones As per the MUTCD, five categories of work duration are defined: Long-term stationary is work that occupies a location more than 3 days Intermediate-term stationary is work that occupies a location more than one daylight period up to 3 days, or nighttime work lasting more than 1 hour Short-term stationary is daytime work that occupies a location for more than 1 hour within a single daylight period Short duration is work that occupies a location up to 1 hour Mobile is work that moves intermittently or continuously.

Long Term Stationary Work (more than 3 days) Typically utilize a full range of TTC procedures and devices Project duration far exceeds installation time of TTC TTC elements may include: Larger channelizing devices, temporary roadways, and temporary traffic barriers Retroreflective and/or illuminated devices

Intermediate-Term Stationary Work (up to 3 days, or nighttime work lasting more than 1 hour) May not be practical to use the same procedures or devices for long-term stationary TTC zones Such as altered pavement markings, temporary traffic barriers, and temporary roadways Increased time to place and remove these devices could significantly lengthen the project, thus increasing exposure time

Short-Term Stationary Work (more than 1 hour within a single daylight period) Most maintenance and utility operations are short-term stationary work Include activities that might involve different treatments Devices having greater mobility might be necessary Signs mounted on trucks Appropriately colored or marked vehicles with rotating/strobe lights may be used in place of signs and channelizing devices May be augmented with signs or arrow panels

Short Duration Work (up to 1 hour) Often takes longer to set up and remove the TTC zone than to perform the work Workers face hazards in setting up and taking down the TTC zone Delays affecting road users are significantly increased when additional devices are installed and removed Simplified control procedures may be warranted for short-duration work Reduction in the number of devices Use of high-intensity rotating, flashing, oscillating, or strobe lights on work vehicles

Mobile Work Often involve frequent short stops for activities Such as litter cleanup, pothole patching, or utility operations, and are similar to short-duration operations TTC zones may includes: Warning signs, high-intensity rotating, flashing, oscillating, or strobe lights on a vehicle, flags, and/or channelizing devices Flaggers A shadow vehicle equipped with an arrow panel or a sign following the work vehicle Appropriately colored and marked vehicles with signs, flags, high-intensity rotating, flashing, oscillating, or strobe lights, truck-mounted attenuators, and arrow panels or portable changeable message signs may follow a train of moving work vehicles

Worker Safety Considerations Key elements that SHOULD be considered to improve worker safety: Training Worker safety apparel Temporary traffic barriers Speed reduction measures Planning of activity area Planning for worker safety Worker safety apparel

Worker Safety Consideration - TRAINING All workers should be trained on: Working safely adjacent to vehicular traffic Work zone traffic control techniques Device Usage Safety devices Traffic control devices Placement of traffic control devices Relevant OSHA Regulation 29 CFR 1926.21, Safety Training and Education

Worker Safety Consideration- WORKER SAFETY APPAREL Workers near motor vehicle traffic should wear bright, visible clothing Relevant OSHA Regulation 29 CFR 1926.95, Criteria for Personal Protective Equipment

Worker Safety Consideration - TEMPORARY TRAFFIC BARRIERS Barriers shall be placed along the work zone depending on: Lateral clearance of workers from adjacent traffic Speed of traffic Duration and type of operations Time of day Volume of traffic Relevant OSHA Regulations 29 CFR 1926.200(g), Traffic Signs 29 CFR 1926.201, Signaling 29 CFR 1926.202, Barricades Concrete Barriers

Worker Safety Consideration SPEED REDUCTION MEASURES Speed of passing motorists may be influenced by: Regulatory speed zoning Funneling Use of law enforcement Lane reduction Presence of flaggers

Worker Safety Consideration PLANNING THE ACTIVITY AREA Plan internal work space and activities Minimize the use of backing maneuvers of construction vehicles Minimize interactions between on-foot workers, equipment and trucks Minimize worker exposure to risk Develop internal traffic control plan and operations Refer to Module 2: Safe Operations and Internal Traffic Control in the Work Space

Worker Safety Consideration PLANNING FOR WORKER SAFETY Hazard assessment should be conducted based on: Characteristics of work site Job classifications required in the work area Must comply with all relevant OSHA regulations Assess worker risk exposures for each job site and job classification 29 CFR 1926.20, General Safety and Health Provisions 29 CFR 1926.20 (b) (2)

Optional Worker Safety Elements Shadow Vehicle with Impact Attenuator Road Closure Police enforcement Additional Lighting Special Devices Rumble strips Changeable message signs Hazard identification beacons Flags Warning lights Intrusion warning devices Rumble strips

Optional Worker Safety Elements - SHADOW VEHICLE Common for mobile and constantly moving operations Should be equipped with: Appropriate lights Warning signs Rear-mounted impact attenuator Shadow vehicle with rear mounted crash attenuator

Truck Mounted Attenuator Crash with a truck with a truck mounted impact attenuator Crash with a truck without an impact attenuator

Optional Worker Safety Elements - ROAD CLOSURE Reduce worker vulnerability to risk of injury Provide more spacious areas to conduct work activities Eliminate threat of intruding vehicles from passing traffic Aid in faster project completion Freeway closure for one direction of traffic

Optional Worker Safety Elements - USE OF POLICE ENFORCEMENT Police units may be stationed in a work zone to: Heighten awareness of passing motorists Improve safety through work zone by enforcing speed limits

Optional Worker Safety Elements - LIGHTING Additional lighting should be provided at work zones that operate during the night Nighttime work requires extra caution due to: Poor night time visibility Impairment of workers related to fatigue Impairment of drivers Nighttime work is common in highway/street construction projects

Sample Work Zone Traffic Control Layout For a Single Lane Closure as per MUTCD Pre-construction speed limit is 70 mph REDUCED SPEED XX AHEAD SPEED LIMIT XX Median REDUCED SPEED XX AHEAD XX Flashing W21-4 W20-5 R2-5b W4-2R R2-1 Arrow Panel G20-2 SPEED LIMIT 1400 700 700 700 700 700 600 KEY Channelizing Devices Sign Location Note: Distance in feet, drawing not to scale

Work Zone Traffic Control MUTCD provides minimum requirements Various demanding situations may warrant enhanced safety precautions, such as: Nighttime work Inclement weather conditions Unusual roadway geometry and environment Combinations of the above Going beyond existing standards/guidelines may be necessary to ensure highest levels of traffic and worker safety

Work Zone Traffic Control Hazards and Injury Prevention Techniques

Hazards of Work Zone Traffic Control Common Hazards Passing motorist intruding into the work space Hazards related to flagging Nighttime hazards

Hazards of Work Zone Traffic Causal Factors Control Conditions unexpected by the moving traffic Violation of driver expectancy Conditions unexpected by the workers Aggressive drivers Unplanned work zone/activity Injuries can occur due to Motorists mistakes Workers mistakes Deficiencies in the work zone environment

General Preventive Measures Traffic Control Use additional warning devices Maintain signs properly Use Proper lane markings On-foot workers Flaggers Use portable radio Use a flashing communication slow/stop paddle equipment Law enforcement Use officers and radar surveillance for traffic speed control

Hazard: Passing Motorists Intruding Into Work Space Causes of Hazards High approach speed Improper geometry of the lane shift Improper traffic control Inadequate information system Hazard mitigation measures Use of proper speed reduction methods Proper design of the wok zone Provide effective traffic control measures No physical separation between work space and traffic lane

Hazard: Passing Motorists Intruding Into Work Space Preventive Measures: Exceed minimum standards/guidelines for traffic control Rumble strips Lane drop arrows Lighted raised pavement markers Radar triggered speed display Safety warning system Combinations of the above Truck may intrude into the work zone

Sample Work Zone Traffic Control Layout With Additional Safety Features For a Single Lane Closure Retroreflective Raised Pavement Markers Temporary Rumble Strips White Pavement Markings Symbol Increase Buffer Area Your Speed is XX Radar Triggered Speed Display REDUCED SPEED XX AHEAD SPEED LIMIT W21-4 W20-5 R2-5b W4-2R R2-1 XX Flashing Arrow Panel G20-2 D D D D D L D KEY : Channelizing Devices Truck Mounted Attenuator D Sign Location Distance Between Traffic Control Devices L Length of Longitudinal Buffer Space

Innovative Technologies for Hazard Control Vertical safetycade CB wizard alert system Radar triggered speed display White lane drop arrows Lightguard lighted raised pavement markers Removable orange strips Flashing slow/stop paddle

Vertical Safetycade Designed to replace standard channelizing devices Benefits: Better visibility More positive guidance Greater portability Improved recoverability Collapsible frame Vertical Safetycades

CB Wizard Alert System Trailer-mounted system Broadcasts a recorded message to all CBequipped motorists Notify drivers of downstream work zones Allows truck drivers to lower their speeds in advance of work zone CB Wizard Advanced Warning Unit CB Wizard Unit

Radar-Triggered Speed Display Back-lit dynamic speed display Standard speed limit sign Strobe flash (optional) Strobe will flash when a vehicle exceeds a certain speed Trailer mounted

Alert driver in advance of lane closure Lane Drop Arrows Encourage drivers to reduce speed and move to the open lane

Lightguard Lighted Raised Pavement Markers Provide greater visibility in work zones Can be: Flashing lights Racing lights Steady-burn lights With Lightguard Lighted Raised Pavement Markers Without Lightguard Lighted Raised Pavement Markers

Removable Orange Rumble Strips Alert motorists of a work zone Benefits: Highly visible Repeating rumble sound Vibration of the steering wheel Easy to install and remove Reduce approach speed

Flashing Slow/Stop Paddle Consists of a standard paddle with a strobe light mounted on its face Increases flagger visibility to passing motorists

Hazard: Flagging Operation 20 flaggers die each year from being struck by a motorist Nonstandard paddle height Flagging can be hazardous as a result of: High speed of passing traffic Aggressive drivers in traffic stream Insufficient stopping sight distance for motorists Improper procedures used by flaggers Not wearing personal protective equipment Inattention Use of nonstandard equipment Improper flagging techniques Hazardous environmental conditions Fog, obstructions, wet pavements Paddle inclined

Injury Prevention Techniques for Flaggers Wear high visibility clothing Appropriate for expected weather (rain gear, warm coat, etc.) High visibility hard hat Use a standard SLOW/STOP paddle or flag Flags are for emergency purposes only

Injury Prevention Techniques for Flaggers STAY ALERT, keep focused on your work Stand alone on shoulder in clear view, not in the open traffic lane Plan an escape route for emergencies Stay in communication with the other flaggers Treat motorists with respect Obtain proper training for flaggers, including safety training

Injury Prevention Techniques for Flaggers Flaggers must avoid Standing where the flagger can be hit by a vehicle Standing in the shade, around a sharp curve Standing in a group Standing near equipment Making unnecessary conversation Reading or day dreaming Listening to music or using ear phones Turning their back to approaching traffic

Hazard: Nighttime Traffic Control Nighttime traffic control is more challenging Poor visibility for drivers Poor visibility for workers Impaired or drowsy drivers Sleep deprived workers

Nighttime Traffic Control Injury Prevention Use special precautions for nighttime traffic control Retro-reflective clothing Flashing lights on body/clothing Retro-reflective tape on equipment Good work area lighting

Summary of the Module Work zone traffic creates serious hazards for motorists and workers Provisions of MUTCD may not be sufficient for preventing injuries/fatalities of on-foot workers Additional injury prevention techniques should be implemented to prevent injuries to on-foot workers Positively guiding traffic through the complex work zone is the key to safety