Module 1: Work Zone Traffic Control

1. Module 1: Work Zone Traffic Control

2. 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

3. 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

4. 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

5. 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

6. 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

7. Components of Temporary Traffic Control Zones (Source: MUTCD 2003) • Advanced Warning Area • Transition Area • Activity Area • Work space • Traffic space • Buffer space • Termination Area

8. 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

9. ‘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

10. 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

11. 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”

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

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

14. 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

15. 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.

16. 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

17. 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

18. 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

19. 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

20. 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

21. 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

22. 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

23. 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

24. 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

25. 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

26. 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”

27. 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)

28. 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

29. 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

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

31. 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

32. 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

33. 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

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

35. 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

36. Work Zone Traffic Control Hazards and Injury Prevention Techniques

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

38. Hazards of Work Zone Traffic Control Causal Factors • 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

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

40. 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

41. 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

42. REDUCED SPEED SPEED LIMIT XX XX AHEAD AHEAD Sample Work Zone Traffic Control Layout With Additional Safety Features • For a Single Lane Closure Retroreflective Raised Pavement Markers Radar Triggered Your Your Temporary Rumble White Pavement Increase Buffer Speed is Speed is Speed Display XX XX Strips Markings Symbol Area REDUCED REDUCED SPEED SPEED SPEED SPEED LIMIT LIMIT XX XX XX XX Flashing AHEAD AHEAD R2 - 5b G20 G20 - - 2 2 R2 - 1 W20 - 5 W4 - 2R W21 - 4 Arrow Panel D D D D D D D L Truck Mounted Attenuator

43. 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

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

45. CB Wizard Alert System • Trailer-mounted system • Broadcasts a recorded message to all CB-equipped 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

46. 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

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

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

49. 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

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