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Page 9
Suggested Citation:"Chapter 2 - Risk." National Academies of Sciences, Engineering, and Medicine. 2012. A Guidebook for Nighttime Construction: Impacts on Safety, Quality, and Productivity. Washington, DC: The National Academies Press. doi: 10.17226/22723.
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Page 9
Page 10
Suggested Citation:"Chapter 2 - Risk." National Academies of Sciences, Engineering, and Medicine. 2012. A Guidebook for Nighttime Construction: Impacts on Safety, Quality, and Productivity. Washington, DC: The National Academies Press. doi: 10.17226/22723.
×
Page 10
Page 11
Suggested Citation:"Chapter 2 - Risk." National Academies of Sciences, Engineering, and Medicine. 2012. A Guidebook for Nighttime Construction: Impacts on Safety, Quality, and Productivity. Washington, DC: The National Academies Press. doi: 10.17226/22723.
×
Page 11
Page 12
Suggested Citation:"Chapter 2 - Risk." National Academies of Sciences, Engineering, and Medicine. 2012. A Guidebook for Nighttime Construction: Impacts on Safety, Quality, and Productivity. Washington, DC: The National Academies Press. doi: 10.17226/22723.
×
Page 12
Page 13
Suggested Citation:"Chapter 2 - Risk." National Academies of Sciences, Engineering, and Medicine. 2012. A Guidebook for Nighttime Construction: Impacts on Safety, Quality, and Productivity. Washington, DC: The National Academies Press. doi: 10.17226/22723.
×
Page 13
Page 14
Suggested Citation:"Chapter 2 - Risk." National Academies of Sciences, Engineering, and Medicine. 2012. A Guidebook for Nighttime Construction: Impacts on Safety, Quality, and Productivity. Washington, DC: The National Academies Press. doi: 10.17226/22723.
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Page 14

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9 Since the latter half of the 20th century and the beginning of the 21st century, urban traffic congestion has increased. The need for highway rehabilitation and maintenance work has further added to the traffic-congestion situation. Therefore, STAs are requiring that more projects be constructed during reduced traffic hours—including nights—as a means of reducing work-zone impacts on traffic flow. Nighttime construction introduces numerous risks to a construction project. One clear set of examples is driver and worker fatigue and reduced visibility, which are factors that could increase safety risks. Night work, because of reduced visibility, creates a situation in which it is more likely to have vehicle intrusions into work zones and construction equipment intrusions into traffic lanes. In addition, the risk of driver error is higher at night. Both transportation officials and contractors find it crucial to understand and appreciate the severity and degree of nighttime work-zone impacts on both the public and the project workforce. Other major factors contributing to the risks of nighttime work are human factors such as sleep, stress, work, social/domestic issues, and psychological characteristics, such as appetite and safety. Additional factors associated with the risks of nighttime construction work zones are reduced work space for machinery and equipment movement, inadequate lighting, high speed of traffic during the night, and long working hours (12 to 14 hours) (Holguin-Veras et al. 2001). Reports show that shift work in general can impair overall worker alertness, reaction times, and even motor skills (Ullman et al. 2006). Many diverse strategies to mitigate risks need consideration when deciding to complete construction tasks at night, so the risk analysis process needs to begin in the early stages of project development. Decisions during project scoping and design, as well as in development of the traffic management plan, all affect jobsite risk. Numerous resources are available from the Federal Highway Administration (FHWA) and other transportation agencies to help orga- nizations mitigate nighttime construction risks. Different factors, such as quality and productivity, which can have an impact on nighttime construction activities, are presented throughout this Guidebook. Each factor can be seen as a risk topic and many different methods are available for addressing them as risks. Risk Management Process The best way to address nighttime construction work-zone risks and hazards is through risk management programs. It is suggested that agencies and contractors begin their risk manage- ment processes early and review the risk management program carefully prior to beginning nighttime work. C H A P T E R 2 Risk

10 A Guidebook for Nighttime Construction: Impacts on Safety, Quality, and Productivity Key Take-Aways • Accident rates for work zones with lane closures are 75 percent higher than those for work zones without lane closures (Cottrell 1999). • Planning for safe night operations needs addresses both construction vehicles and traffic. Risk management is the term used to describe a sequence of analysis and management activi- ties focused on identifying and creating a response to risks and, in the case of nighttime construc- tion, to project-specific risks. Various organizations use very similar steps, but slightly different terms, to describe their risk management approach. These are the important risk management steps: 1. Risk identification. 2. Risk assessment/analysis. 3. Risk mitigation and planning. 4. Risk allocation. 5. Risk monitoring and control. Risk identification is the process of determining which risks might affect the project and docu- menting their characteristics using tools such as brainstorming and checklists. Risk assessment/analysis involves the quantitative or qualitative analysis that assesses impact and probability of risk. Risk mitigation and planning involves analyzing risk response options (acceptance, avoidance, mitigation, or transference) and deciding how to approach and plan risk management activities. Risk allocation involves placing responsibility for a risk on a specific party or parties—typically through a contract. The fundamental tenets of risk allocation include allocating risks to the party that is best able to manage them, allocating risks in alignment with project goals, and allocating risks to promote team alignment with customer-oriented performance goals. Risk monitoring and control is the capture, analysis, and reporting of project performance, usu- ally as compared to the risk management plan. Risk monitoring and control assists in tracking and resolution. Key Take-Away Risk assessment should begin early when making the decision to use nighttime construction. Understanding that the risk management process is repetitive and cyclical is important. As the project evolves, some risks will be resolved or diminished, while others may surface and need to be addressed. The five fundamental risk management steps need to be applied throughout the project life cycle for a successful project. The extent of application of each step varies as the methods and tools used to support these steps depend on the project development phase and project complexity (Molenaar et al. 2010). 1. Risk Identification Risk management is especially important with nighttime work. Risk management planning for nighttime construction should begin with identification of risks that may affect the work and the traveling public. Risk identification can be accomplished through peer reviews of project documentation, studies, reports, preliminary plans, estimates, and schedules and should pro- duce a comprehensive checklist of possible risks. The risk identification process begins with the team compiling a list of the project’s pos- sible risks. The identification process varies depending on the nature of the project, but most

Risk 11 identification processes begin with an examination of issues and concerns created by the project development team. Issues and concerns can be derived from an examination of the project description, work break- down structure, cost estimate, design and construction schedule, procurement plan, or general risk checklists. Checklists and databases can be created for recurring risks, but project team experience and subjective analysis is usually required to identify project-specific risks (Molenaar et al. 2010). Teams must be cautious not to overlook risks or focus on solving problems during the risk identification process. Engineers and project managers inherently have an optimistic bias when thinking about uncertain items or situations, because they are, by nature, problem solvers. During the identification stage, the focus is on numerating risks, not on mitigating them. Opportunities and solutions are addressed later during the mitigation process. 2. Risk Assessment/Analysis Once risks are identified, teams can perform qualitative and quantitative risk analysis to assess the impact and likelihood of the identified risks. During qualitative risk analysis, identified risks are assessed for their probable occurrence and how they impact the work or the public. That said, risk assessment has two aspects. The first determines the likelihood of a risk occur- ring (risk frequency) and classifies it along a continuum from very unlikely to very probable. The second aspect judges the impact of the risk should it occur (consequence severity). Risks can affect projects in diverse ways. The effects of risks are usually apparent in project outcomes by increasing cost or schedule directly. However, some risks influence the project by affecting the public, public perception, the environment, or safety and health considerations. Some of the qualitative risk assessment techniques include recording risk details and rela- tionships and ranking risks relative to each other, while quantitative risk analysis helps assess, through numeric estimation, the probability of the nighttime activity meeting the project cost and schedule. Numeric estimation can be done with the use of Monte Carlo simulation, which is a quantitative tool for analyzing project risks and uncertainties, for example. 3. Risk Mitigation and Planning The objectives of risk mitigation and planning are to explore risk response strategies for the high-risk items identified in the qualitative and/or quantitative risk analysis. The process iden- tifies and assigns responsibility for each risk, ensuring that each significant risk has an owner. The owner of the risk could be an agency planner, engineer, or construction manager. The owner might even be an insurance company, depending on the point in project development, or it could be a private-sector contractor or partner, depending on the contracting method and risk allocation. Key Take-Away Formalizing risk mitigation and planning throughout an agency establishes a risk culture that results in better cost management from planning through construction. 4. Risk Allocation After the team identifies and analyzes the project risks, it is essential to determine the appro- priate and most suitable actions for mitigation to reduce the threats that the risks impose on the nighttime work (i.e., through increased cost or increased safety measures). The process

12 A Guidebook for Nighttime Construction: Impacts on Safety, Quality, and Productivity involves assigning responsibility to the various parties to implement the decided-upon mitiga- tion strategies. Finally, the contract is a risk allocation vehicle. By defining roles and responsibilities, the con- tract assigns risks. Risk allocation in any contract affects cost, time, quality, and the potential for disputes, delays, and claims. Key Take-Away Contractual misallocation of risk has been found to be a leading cause of construction dis- putes in the United States (Smith 1995). 5. Risk Monitoring and Control Through the risk monitoring and control stage, the parties will continuously monitor the risks and, if possible, identify any potential new risks. The objectives of risk monitoring and control are as follows: • Track the identified risks systematically. • Identify any new risks. • Manage the contingency reserve established for the project effectively. • Capture lessons learned for future risk assessment and allocation efforts. Risk monitoring and updating occurs after the risk mitigation and planning processes. It precedes the risk allocation process in the planning phase, but it is performed in conjunction with allocation during the programming and design phases. Risk monitoring and control must continue for the life of the project because risks are dynamic and the list of risks and associated risk management strategies will likely change as the project develops and new risks evolve or anticipated risks disappear. Periodic project risk reviews repeat the tasks of identification, assessment, analysis, mitigation, planning, allocation, and monitoring and control. Regularly-scheduled project risk reviews can be used to ensure that project risk is an agenda item at all project development and construction management meetings. If unanticipated risks emerge, or a risk’s impact is greater than expected, the planned response or risk allocation may not be adequate. At this point, the project team must perform additional response planning to control the risk. Key Take-Away All identified risks need to be managed according to the developed risk plan and the status of each risk needs to be monitored continuously throughout the project. Tip Budget time, money, and staff for risk assessment, risk management, and risk response activities. Resources • Association for the Advancement of Cost Engineering (AACE) International. 2000. AACE International’s Risk Management Dictionary. Cost Engineering Journal. 42(4):28–31. • Department of Energy. 2003. Project Management Practices, Risk Management. U.S. Depart- ment of Energy. Office of Management, Budget and Evaluation. Office of Engineering and Construction Management. Washington, DC.

Risk 13 • Project Management Institute. 2004. A Guide to Project Management Body of Knowledge (PMBOK® Guide). The Project Management Institute. Newton Square, Pennsylvania. 388 pp. Types of Risks To reiterate, the first step in an effective risk management program is to identify possible risks. Specific concerns related to nighttime work zones include poor visibility and work qual- ity, staffing issues, unwanted noise and glare, decreased worker and driver alertness, impaired drivers, higher vehicle speeds, increased labor costs, materials and traffic control, and problems in logistics and supervision. These risks are categorized broadly as safety, cost/production and schedule, quality, organizational relationships, technical, construction, economic, and environ- mental. Table 2.1 provides more detail by risk category and where additional information can be found in this Guidebook. Tip Mobile night operations such as painting and patching pose an increased risk to road users and workers because it is rarely feasible to use standard lane closures, visibility is lessened, and driver performance is often decreased. High priority should be given to the use of shadow vehicles with truck-mounted attenuators during all mobile night operations on moderate and high-speed highways (Bryden 2003). Summary STAs are shifting toward more nighttime construction. Nighttime construction mitigates the impact of construction operations on the traveling public, can shorten the duration of construc- tion operations, and decreases interruptions to construction activities. However, nighttime construction operations may be more hazardous for both drivers and construction personnel. Therefore, risk management is extremely important for creating a safe nighttime work zone and successful project. Although this Guidebook gives an overall idea of the general types of risks that may be involved in nighttime work zones, it should not be followed blindly for all projects. Given that each con- struction project is unique in nature, the types of risks involved in projects vary from project to project according to the type of project, site conditions, different contract types, contractors and subcontractors involved, and political scenario. It is extremely important to have a good risk management team assigned for all construction projects. The team should be responsible for identifying and assessing risks according to the specific project and for creating a risk mitigation process. The risk management team will ideally start work during project conceptualization and continue until project commissioning. Proper risk management provides safe work zones for workers, a safe travelway for motorists, and a successful project.

14 A Guidebook for Nighttime Construction: Impacts on Safety, Quality, and Productivity Potential Risks Additional Information Safety • Vehicle intrusions into the work zone • Workers struck by construction equipment • Construction equipment intrusion into the operational traffic lanes • Irresponsible driver behavior • High speed of vehicles tr aversing the work zone • Driver confusion • Poor visibility • Irresponsible worker behavior • Inadequate lighting • Worker fatigue (Elrahman and Perry 1994) Chapter 8 of this Guidebook has additional safety risk information. Cost/Production and Schedule • Temporary lighting • Additional traffic control measures • Inadequate lighting • Poor visibility • Poor worker morale and fatigue • Availability of supplies and materials • Additional time to set up and take down traffic control devices • Additional time to set up and take down lighting equipment • Coordination with day work activities Chapter 5 of this Guidebook has additional productivity information and Chapter 7 discusses costs. Quality • Lower quality • Poor visibility • Lighting deficiencies • Difficulty achieving good supervision and inspection • Poor worker morale • Temperatures Chapter 6 of this Guidebook includes additional information on quality. Organizational Relationship • Lack of communication • Availability of agency decision makers • Availability of design consultants Chapter 9 of this Guidebook includes information on communication strategies. Technical • Failure to adequately understand circumstances of nighttime work • Modification of specifications for differences Chapter 3 of this Guidebook has information on illumination. Construction • Productivity • Quality This Guidebook addresses productivity and quality risks in chapters 5 and 6, respectively. Economic • Construction costs • User costs • Accident costs Chapter 7 of this Guidebook includes information about the various costs of nighttime work. Environmental • Public relations • Lighting • Community concerns This Guidebook addresses environmental risks in the Illumination, Nuisances, and Communications chapters (3, 4, and 9). Table 2.1. Potential nighttime construction risk details by category.

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TRB’s National Cooperative Highway Research Program (NCHRP) Report 726: A Guidebook for Nighttime Construction: Impacts on Safety, Quality, and Productivity provides suggested guidance on the conduct of nighttime highway construction and maintenance operations.

These guidelines are based on best practices and strategies for nighttime operations that relate to the safety of workers and the traveling public as well as the quality of the as-built facility. The guide also addresses work-zone risk analysis planning and implementation, construction nuisances to both neighbors and workers, and work-zone illumination methods.

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