Browsing by Subject "Work zone safety"

Now showing 1 - 12 of 12
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    Design and Development of a Visual Warning System for Worker Safety On Roadside Work zones
    (2016-09) Abbaszadeh Banaeiyan, Nazanin
    Growing traffic on US roadways and heavy construction machinery on road construction sites pose a critical safety threat to construction workers. This writing summarizes the design and development of a worker safety system using Dedicated Short Range Communication (DSRC) to specifically address the workers’ safety for the workers working around the heavy machinery. The proposed system has dual objectives. First objective is to improve workers’ safety by providing visual guidance to the operators of the construction vehicles about the workers’ presence in the vicinity. This visual guidance keeps the operators of the heavy machinery well informed about the whereabouts of the workers in close proximity while operating the heavy vehicle. The second objective of the proposed system is to improve the work-zone traffic mobility by dynamically posting suitable speed limits and other warning messages on the DSRC-equipped variable message signs (VMSs) depending on the workers’ presence in an active work-zone to appropriately warn the drivers of the passing-by vehicles. A prototype was developed and field tests were conducted to demonstrate and evaluate the performance of the proposed system. The evaluation test results show that the system can successfully identify the presence of workers around a construction vehicle on an Android tablet with acceptable distance (1.5 – 2 m) and direction (1-5 degrees) accuracies. Furthermore, the test results show that a DSRC equipped VMS can successfully post a suitable speed limit corresponding to the presence of workers in its vicinity.
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    Development of a Mobile App for Reporting Work Zone Intrusions
    (Minnesota Department of Transportation, 2024-01) Davis, Brian; Morris, Nichole L.; Craig, Curtis; Schumacher, John; Khoday, Annaika
    Work zone intrusions represent a significant safety risk to workers. To help better understand these situations, the Minnesota Department of Transportation partnered with the University of Minnesota to create a method to document intrusion events. This information provides a deeper understanding of the circumstances under which these events occur and enables data-driven decision making when considering ways to reduce or mitigate work zone intrusions. This work focuses on the development of a mobile smartphone app that allows workers to report intrusions from the field immediately after they occur, allowing for timely and accurate intrusion reporting. The work zone intrusion mobile app is developed using an iterative, user-centered design process that solicits feedback from work zone personnel, supervisors, and work zone safety stakeholders at every step in the process. The app uploads completed report data to the existing eSAFE system, allowing for a single repository of collected intrusion report data. To support deployment of the system, training workshops and supporting training and communications materials are created for distribution among users. Throughout the development and deployment of the app, user feedback shows that the app is easy to use and well liked.
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    Directional Sound for Long Distance Auditory Warnings from a Highway Construction Work Zone
    (University of Minnesota Center for Transportation Studies, 2008-12) Phanomchoeng, Gridsada; Rajamani, Rajesh; Hourdos, John
    Directional sound can be used as a warning signal to denote that failure to follow an indicated action could result in serious accidents. In some applications such as to alert a vehicle that is likely to intrude into a highway construction work zone, long distance auditory warnings are necessary. In such cases, directed sound could be utilized to warn the specific vehicle without disturbing other vehicles on the highway. This report reviews the currently available scientific technologies that can potentially be used to develop a long distance auditory warning system for highway work zone applications. Of these, ultrasound based parameter arrays and time delay controlled arrays of compact ordinary speakers are taken up for detailed analysis and experimental evaluation. An ultrasound based parametric array is the most appropriate technology for generating highly directional sound. However, if cost, installation, maintenance, and price are considered, the most suitable technology is found to be arrays of flat panel loudspeakers with time delay control. Such a system can be used to generate directional sound effectively for long distance auditory warnings.
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    Evaluation of the Smart Work Zone Speed Notification System
    (Minnesota Department of Transportation., 2019-06) Hourdos, John; Parikh, Gordon; Dirks, Peter; Lehrke, Derek; Lukashin, Pavel
    The Smart Work Zone Speed Notification (SWZSN) system aims to alleviate congestion, queuing, and rear end crashes in work zones by informing drivers of the speed of the downstream segment using a type of portable Intelligent Lane Control System (ILCS), Portable Changeable Message Signs (PCMS). The hypothesis was that drivers, knowing the speed up to 1 mile downstream, will slow down early or at least be alert and perform smoother decelerations. Video of the SWZSN was analyzed over two years of operation by the Minnesota Traffic Observatory. Overall, the system resulted in beneficial reductions of selected decelerations by the drivers. In situations where the messages communicated to the drivers were consistent and accurate, reductions of more than 30% in the selected deceleration rates were observed. Unfortunately, there were several cases where counterproductive or misleading messages were communicated to the drivers, prompting relative increases to the selected deceleration rates. The most important observation, stemming from both positive and negative influences, was that the speed notification system was noticed by drivers and resulted in a statistically significant influence on driving behavior, unlike other driver alert systems.
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    Evaluation of Workforce Perceptions as a Means to Identify and Mitigate the Causes of Musculoskeletal Disorders
    (Minnesota Department of Transportation Research Services Section, 2010-01) Loushine, Todd William
    An analysis of workers’ compensation data showed that five job classifications accounted for over 93% of all cases. This analysis also showed that 48% of the cases resulted in sprains and strains, and 70% of those cases were caused by over-exertion and/or awkward work postures. Based on these findings, a research proposal was created to investigate worker perceptions of potential musculoskeletal injury factors and possible corrective actions. Fifty randomly-selected Mn/DOT transportation generalists and mechanics from District 1 were interviewed via telephone. Interviews were voice recorded, transcribed, and analyzed by shortening and separating responses. Each of the six questions produced between fifteen to twenty-one response categories and total response counts between 63-to-123. The most frequently cited safety concern was exposure to public traffic on road projects; followed by heavy or awkward lifting, “rushing” to get a job done and exposure to typical construction site hazards. Overall, workers felt management and co-workers were committed to safety on the job. Possible safety improvements revolved around: general awareness, watching out for each other, planning ahead, taking time to do the job right, and proper use of personal protective equipment. Most of the workers interviewed indicated interest in participating and promoting a workplace wellness program to improve their health and fitness. Efforts to reduce musculoskeletal injuries need to incorporate the concerns and ideas of workers, building off of what was learned in this study.
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    Flagger Operations: Investigating Their Effectiveness in Capturing Driver Attention
    (Minnesota Department of Transportation, 2017-02) Harder, Kathleen; Hourdos, John
    This two-pronged (driving simulation and field study) investigation of driver behavior in work zones contributes basic and applied knowledge to our understanding of work zone safety. In the driving simulator study, a fully interactive PC-based STISIM driving simulator was used to test the effectiveness of roadway elements designed to capture and sustain the attention of drivers in flagger-operated work zones. The participants were 160 licensed drivers from four age groups: 18-24, 32-47, 55-65, and 70+ years of age. Each participant drove each of the three conditions in counterbalanced order. The driving simulator study revealed that the new set of elements is more effective than the elements currently used to reduce driving speeds on the approach to a flagger-controlled work zone. No difference in mean driver speed was found in response to the sign with an LED presence. The dynamic speed display coupled with the horn is more effective than the dynamic speed display alone. The cognitively engaging elements identified as effective in the driving simulator study were tested in two field operational tests. The field tests revealed that all but one of the elements identified in the experimental driving simulator study were effective. In particular, the findings revealed that a combination of the speed trailer and horn barrel are effective in reducing the overall speed of vehicles approaching the field study work zone. The field test revealed that the new experimental layout practically eliminated high-speed outliers in addition to its success in reducing driver approach speed to the flag operator.
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    Portable, Non-Intrusive Advance Warning Devices for Work Zones with or without Flag Operators
    (Minnesota Department of Transportation Research Services, 2012-10) Hourdos, John
    The main objective of this study was to develop a work zone alert system informing speeding drivers of the upcoming work zone and raising their attention level before they reach the taper line and/or the work zone flag operator. The resulting system, termed Intelligent Drum Line (IDL), is capable of delivering visual and auditory warnings, targeting vehicles that are exceeding the posted or temporary speed limit upstream of the work zone. The IDL system, in its final incarnation, is the best compromise that can be reached between developing a low-cost system that is rugged enough to be deployed on the shoulder of high-speed roadways and comprised of as few individual parts as possible so a single work zone worker can deploy and move the system as the work zone operations are progressing and delivery of a warning targeted only at vehicles that are going faster than the desired speed set by the work zone crew. The IDL system has been tested in the MnROAD facility, targeting vehicles ranging from regular passenger vehicles to a 3-ton snowplow truck. The auditory warning has been successful in penetrating the vehicle cab and loud enough to attract the attention of the driver. Although, still in a prototype stage, the IDL system has received high marks from MnDOT engineers and work zone workers. Further development is needed to ensure that the final product is crash proof and that it can be produced efficiently.
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    Test and Evaluate a Bluetooth Based In-Vehicle Message System to Alert Motorists in Work Zones
    (Center for Transportation Studies, University of Minnesota, 2019-05) Liao, Chen-Fu
    Safe and efficient traffic flow in a work zone is a major concern for transportation agencies. To reduce risky behavior around work zones, we have developed a prototype system to investigate the feasibility of using in-vehicle messages to increase drivers’ awareness of safety-critical and pertinent work zone information. Our previous effort focused on an inexpensive technology based on Bluetooth low energy (BLE) beacons that can be deployed in or ahead of the work zone. A smartphone app, called WorkzoneAlert, was developed to trigger non-distracting, auditory messages in a smartphone mounted in a vehicle within range of the BLE beacons. Messages associated with BLE beacons around the work zone can be updated remotely in real time and thus could provide significantly improved situational awareness about dynamic conditions in work zones, such as awareness of workers on site, changing traffic conditions, or hazards in the environment. We incorporated the recommended in-vehicle message elements and user interface from a human factors study previously conducted by the HumanFirst lab and deployed the in-vehicle work zone information system at three construction sites (CSAH 53, CSAH 112, and MN-65) in the Twin Cities metropolitan area (TCMA). Our field test results indicated that the WorkzoneAlert app is able to reliably detect the BLE beacon placed an average of 127 m away on traffic signs or portable radar speed signs and successfully announce the corresponding message associated with each BLE beacon.
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    User-centered Smart Traffic Sign Development Study
    (Minnesota Department of Transportation, 2023-06) Morris, Nichole L.; Rajamani, Rajesh; Drahos, Bradley A.; Xie, Zhenming; Alexander, Lee; Kessler, William
    Flaggers protect workers by providing temporary traffic control and maintaining traffic flow through a work zone. They are often the first line of defense to stop distracted, inattentive, or aggressive motorists from intruding into the work area. This project aims to develop an automated intrusion detection system to alert drivers who are unsafely approaching or entering a flagger-controlled work zone. A human factors user needs assessment found maintenance workers preferred a modified traffic signal to feature the alert system due to flagger risks of being in the roadway and drivers failing to stop and remain stopped when presented with the STOP side of the flagger sign. A modified traffic signal that could be operated using a handheld remote was developed. The low-cost embedded electronics on the traffic signal enabled it to track trajectories of nearby vehicles, detect potential intrusions, and trigger audio-visual warnings to alert the intruding driver. Usability testing in a simulated driving test found poor expectancies and stopping rates of the traffic signal-based alarm system compared to a traditional flagger but did demonstrate evidence that drivers may be less likely to stop and remain stopped with the flagger STOP sign than the red ball indicator of the traffic signal. Furthermore, some drivers corrected their initial stopping error after triggering the auditory alarm of the traffic signal. A follow up test found improved performance with the alert system incorporated into an audiovisual enhanced STOP/SLOW flagger paddle. Testing of the developed sensor system found the system capable of simultaneous multivehicle tracking (including estimation of vehicle position, velocity, and heading) with a range of up to 60 meters and angular azimuth range of 120 degrees and correctly detecting all test intruding vehicles.
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    Visual Warning System for Worker Safety on Roadside Workzones
    (Minnesota Department of Transportation, 2016-08) Banaeiyan, Nazanin; uz Zaman, Attiq; Hayee, M.Imran
    Growing traffic on US roadways and heavy construction machinery on road construction sites pose a critical safety threat to construction workers. This report summarizes the design and development of a worker safety system using Dedicated Short Range Communication (DSRC) to specifically address the workers’ safety for the workers working around the heavy machinery. The proposed system has dual objectives. First objective is to improve workers’ safety by providing visual guidance to the operators of the construction vehicles about the workers’ presence in the vicinity. This visual guidance keeps the operators of the heavy machinery well informed about the whereabouts of the workers in close proximity while operating the heavy vehicle. The second objective of the proposed system is to improve the work-zone traffic mobility by dynamically posting suitable speed limits and other warning messages on the DSRC-equipped variable message signs (VMSs) depending on the workers’ presence in an active work-zone to appropriately warn the drivers of the passing-by vehicles. A prototype was developed and field tests were conducted to demonstrate and evaluate the performance of the proposed system. The evaluation test results show that the system can successfully show the presence of workers around a construction vehicle on an Android tablet with acceptable distance (1.5 – 2 m) and direction (15 – 20 degrees) accuracies. Furthermore, the test results show that a DSRC-equipped VMS can successfully post a suitable speed limit corresponding to the presence of workers in its vicinity.
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    Work Zone Intrusion Report Interface Design
    (Minnesota Department of Transportation, 2018-02) Craig, Curtis M.; Morris, Nichole L.; Libby, David A.; Davis, Brian
    While necessary for roadways, work zones present a safety risk to crew. Half of road workers deaths between 2005 and 2010 were due to collisions with motorists intruding on the work zone. Therefore, addressing intrusions is an important step for ensuring a safe work environment for crewmembers. However, a recent research synthesis at the Minnesota Department of Transportation found that few states had an explicit method for systematically collecting work zone intrusion data. The purpose of this work zone intrusion interface design project was to design an efficient, comprehensive, and user-friendly reporting system for intrusions in work zones. A user-centric, iterative design process was employed to design an adaptable web-based and paper report to account for simple documentation of intrusions not deemed a threat to worker safety and a detailed report for more thorough documentation of serious intrusion events. Final recommendations include organizational changes and support to encourage workers to complete the form and provide valuable data to the state.
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    Work Zone Mapping and Tag Deployment System
    (Center for Transportation Studies, University of Minnesota, 2019-10) Parikh, Gordon; Duhn, Melissa; Loutfi, Andrew; Hourdos, John
    Roadway construction is an inevitable part of functional transportation infrastructure. However, work-zone incidents have increased overthe years. This report is the third part of an interdisciplinary project to improve driver safety in work zones. The first component was ahuman factors study, performed by Craig et al. (2017), determining the most effective way to alert drivers to work zones without disrupting driver behavior. The second component, by Liao (2019), sought to determine whether Bluetooth low-energy tags could be deployed in work zones to provide real-time updates to drivers’ mobile phones through an app. The third component, the Statewide Work Zone Information System (SWIS), establishes a real-time database of active work zones from the first advanced warning sign being placed to the time the crews pack up. SWIS uses beacons attached to traffic control devices, called assets, that send messages to a central cloud repository. From there, messages are processed, categorized into Projects, Traffic Control Plans, and Work Zones. SWIS continuouslyupdates based on asset messages it receives. Users can access SWIS through a web interface, to view active, past or future projects, plan aproject, or update existing projects. SWIS provides an online, real-time portal for storing, monitoring, and inspecting work zone traffic-control operations.