Hazardous Materials Transportation Research Articles

Equitable routing of rail hazardous materials shipments using CVaR methodology

The low probability – high consequence nature of hazardous materials (hazmat) incidents dictate a risk-averse route planning approach. However, preparing routing plans for multiple hazmat shipments between various origin–destination pairs also raises the question of risk-equity, and not just minimization of hazmat risk. Hence, the objective is to plan an equitable routing plan for different rail hazmat shipments while not only ensuring the safety of citizens but also precluding certain population zones from being subjected to intolerable levels of hazmat risk. To this end, we propose an analytical framework that makes use of a conditional value-at-risk (CVaR) measure of risk to generate minimum risk shipment routes while promoting risk-equity in both the arcs and the yards of the railroad network. While the commercial solver, CPLEX, lacks the ability to generate integer solutions for even small problem instances, a Lagrangian relaxation method aimed at being maximized using the Subgradient optimization algorithm is applied to provide a lower bound. The proposed framework is finally used to study several problem instances using the realistic infrastructure of a railroad operator, and to conclude that risk-equity can be achieved by re-routing, and that the design of train services along with the trade-off between yard-risk and arc-risk determine the number of re-routing and the optimal value of CVaR.

On Comparing the Similarity and Dissimilarity Between Two Distinct Vehicular Trajectories

In this paper, we study the problem of comparing the similarity and dissimilarity between two distinct vehicular trajectories by proposing an adjacency-based metric. This approach has a broad application in building truthfulness by comparing the similarity between two vehicles and evaluating the dissimilarity between two distinct paths in hazardous materials transportation. Given two sequences $A$ and $B$ of Point of Interests (POIs) visited by two vehicles in a road/transportation network, the problem is to delete some nodes from $A$ and $B$ to obtain $A'$ and $B'$ such that the number of adjacencies in $A'$ and $B'$ is maximized. In the sequences $A'$ and $B'$ duplicated nodes are allowed, e.g., to represent road edges. We prove that this problem is NP-hard when noisy POIs are deleted and all the remaining POIs must be involved in some adjacency. On the other hand, when the adjacency involvement constraint is dropped, a variation of the problem is as hard as Exact Set Cover hence cannot be approximated within a constant factor unless P=NP. At last, we design a practical approach based on local search and show that the algorithm is very effective on simulation data.

ВЛИЯНИЕ ПОВЫШЕННОЙ ТЕМПЕРАТУРЫ НА ДИНАМИЧЕСКИЕ СВОЙСТВА ОСИНЫ

As a damping material in the structures of containers for the transportation of hazardous materials, along with plastic metals, fiber-claydite concrete and synthetic foams, it is proposed to use wood of different species. Since containers are transported in different climate regimes, there is an urgent need to study the properties of wood at elevated temperatures. The paper presents the results of dynamic tests of aspen under uniaxial compression under conditions of temperature increased to +60°C. The tests were carried out according to the Kolsky method on a Hopkinson split-bar setup. To study the anisotropy of properties, aspen samples were made and tested by cutting samples along and across the direction of the grains. As a result of processing the experimental data, dynamic stress-strain curves were obtained. According to the experimental data, there are determined the stresses at which the integrity of the samples were violated. The mean values of the moduli of deformation in the active loading regions of stress-strain curves are also presented. The highest slope of the load sections and the highest breaking stresses were observed for the specimens when loaded along the grains, and the smallest values of these parameters were noted when loaded across the grains. For specimens loaded along grains at strain rates above 1500 s–1, after reaching the limiting stress values, a decrease (relaxation) of stresses is observed with increasing deformations. For specimens loaded across the grains, an almost horizontal section the diagrams of deforming or even with some strengthening is more typical. The effect of elevated temperature on the strength and deformation properties of aspen is estimated. There is a tendency towards some decrease in the diagrams at a temperature of +60 °C in comparison with the diagrams at room temperature. In this case, both the moduli in the loading and unloading sections and the limiting (breaking) stresses decrease. The obtained features of the behavior of aspen specimens at elevated temperatures should be taken into account when modeling deforming wood.

Model za izbor rute za transport opasnog tereta primenom fuzzy logičkog sistema

Introduction/purpose: The paper presents a model for the selection of a route for the transport of hazardous materials using fuzzy logic systems, as a type of artificial intelligence systems. The system presented in the paper is a system for assistance in the decisionmaking process of the traffic service authorities when choosing one of several possible routes on a particular path when transporting hazardous materials. Methods: The route evaluation is performed on the basis of five criteria. Each input variable is represented by three membership functions, and the output variable is defined by five membership functions. All rules in a fuzzy logic system are determined by applying the method of weight premise aggregation (ATPP), which allows the formation of a database based on experience and intuition. Based on the number of input variables and the number of their membership functions, the basic base of 243 rules is defined. Three experts from the Ministry of Defense were interviewed to determine the weighting coefficients of the membership functions, and the values of the coefficients were determined using the Full Consistency Method (FUCOM). Results: A user program which enables the practical application of this model has been created for the developed fuzzy logic system. Conclusion: The user platform was developed in the Matlab 2008b software package.

Explicit and implicit Valuation-Based System methods for the risk assessment of systems subject to common-cause failures under uncertainty

Multiple components within a system may fail or malfunction simultaneously due to a shared cause or common cause (CC). This kind of failure is referred to as a common-cause failure (CCF), and it contributes greatly to the system failure. Due to the insufficiency of relative data and system complexities, different kinds of uncertainties inevitably exist in real-world system modeling. This paper proposes explicit and implicit Valuation-Based System (VBS) methods to model systems subject to CCFs, and to evaluate the failure probability of such systems considering the parametric uncertainty related to state probabilities of components and the model uncertainty related to the system structure. Both methods are suitable to model systems subject to CCFs under different kinds of uncertainties, and allow the relationship among multiple CCs being s-independent, s-dependent or mutually exclusive. Finally, the proposed methods are applied to model hazardous material transportation accidents and to evaluate the occurrence probability of accidents using statistical data.

A multi-objective robust optimization approach for green location-routing planning of multi-modal transportation systems under uncertainty

Carbon emission has been widely studied in transportation research in general, yet research on carbon emission specifically in hazardous material transportation remains surprisingly limited. This study presents a multi-objective model for locating transfer points and routing in a multi-modal network of hazardous materials, accounting for multiple different uncertainties, while minimizing carbon emission alongside risk and cost of transportation. This study models uncertainties in accident probabilities, emission factors, and costs of establishing transfer points with polyhedral uncertainty sets, and utilizes robust counterpart optimization to tackle these uncertainties. The application of the proposed approach is examined in a case study of petroleum product transportation. The results of our analyses confirm the effectiveness and robustness of the developed model. Specifically, it is found that the proposed model can reduce carbon emissions by 873 g, and individuals at risk by 0.28, for every additional dollar spent.

Multi-modal and multi-route transportation problem for hazardous materials under uncertainty

ABSTRACT In this article, the multi-modal and multi-route transportation problem for hazardous materials under uncertainty is studied, and an interval 0–1 integer programming model is proposed to optimize the transportation risks and transportation costs during the transportation of hazardous materials. Factors such as freight rates and loading and unloading costs are different when the transportation modes, transportation time and transportation areas are different. Therefore, some parameters in the model are assumed as interval numbers. The proposed model is transformed to a deterministic model by the interval ranking method. In addition, a genetic algorithm is proposed to solve the model. Finally, a real-world case of the multi-modal and multi-route transportation problem for hazardous materials under uncertainty is studied to demonstrate the rationality and effectiveness of proposed model and algorithm.

Study on multimodal network expansion for hazardous materials based on disruption

This paper studies the multimodal network expansion problem for hazardous materials. In this study, the transportation characteristics of hazardous materials and disruption are considered, the mixed integer probability robust model is established with risk and cost as the objective. A numerical case is solved by CPLEX, and the decision of network expansion and flow distribution is obtained. Through the comparison between the robust model and the traditional model, it is proved that the robust model can complete the transport of hazardous materials in the network with lower cost-risk. The paper also provides advice to decision-makers with different risk preferences through the Pareto frontier.

Comparisons of a Multi-Objective Compromise Weight Model and a Multi-Objective Evolutionary Algorithm in Hazmat Transportation Route Planning

On July 31, 2014, a series of gas pipeline explosions occurred in Kaohsiung City, causing 32 deaths and 321 injuries. Following this accident, the Kaohsiung City government decided to replace the use of pipelines with trucks for transporting hazmat, transfering the risk from beneath the road to the surface. This means that careful consideration needs to be given to safety and cost in hazardous material (hazmat) transportation route planning. The issue of how to design optimal routes for the transportation of hazmat is, therefore, important and involves consideration of various criteria. This research focuses on three objectives: cost, risk, and emergency response capability. It then constructs two solution algorithms, the compromise weight model and the evolutionary algorithm, to solve the multi-objective problem. The results from these two algorithms are observed and compared. In addition, this research also provides some recommendations for stakeholders, including the hazmat industry, government, and residents.

Modern challenges of dangerous and extraordinary goods transportations

Dangerous goods - goods which, by the nature of their physical characteristics, chemical composition, dimensions, or other specific features and nature (live animals or fish), for some reason endanger human life or health, the environment natural or general order or material goods, including those with features of the principles of humanitarianism. The transport of dangerous and oversize goods is one of the most difficult specialties in the field of goods transport in public transport, in particular in road and rail transport. Such transport is regulated by a number of legal acts that do not apply to companies carrying out tasks related to the transport of loads, the so-called neutral. The United Nations has created a closed TN directory, giving everyone a four-digit "UN number", at the same time dividing them into classes depending on the threat or the predominant threat. The provisions of the ADR agreement relate, inter alia, to the rules (requirements) for TN transport in terms of limiting the possible effects of a potential release of hazardous substances (e.g. as a result of road or rail collisions), as well as, above all, the forms and principles of preventing the possibility of such events. The transport of dangerous goods is a special type of transport and it is subject to specific legal provisions, meeting and observing a number of specific requirements. The safety of this type of transport depends on the proper organization of its transport and the maximum involvement of participants in the entire process. The organization of the transport of hazardous materials requires a comprehensive, comprehensive view of the vehicle, packaging and cargo (means of transport and packaging should be adapted to the transported goods) as well as people involved in the preparation of transport, drivers with appropriate authorizations and training, setting the route, securing this routes in terms of maintaining safety in the event of an emergency. The article offers the author's approaches to the investigation of modern challenges of dangerous and extraordinary goods transportations.

Evaluation of Autoclaving CAT: A Infectious Substance Packaging during the Ebola Crisis in the United States

Background: During the 2014 US Ebola crisis, an unprecedented amount of biohazardous waste was generated during patient care; healthcare facilities were overwhelmed by large volumes of waste. Few facilities had on-site waste treatment; therefore, waste was packaged and sent off site for incineration and disposal in Port Arthur, Texas, at a significant cost. Shipping this waste off site required the use of the US Department of Transportation (USDOT) Hazardous Materials (HMR 49 CFR) category A triple packaging for infectious substances. The most common treatment method for biohazardous waste in the United States is via commercial autoclaves. Because Category A waste packaging had not been tested to ensure effective treatment, we conducted autoclave efficacy studies to evaluate the various types of Category A packaging containing surrogate Ebola waste. If successful, this would potentially provide additional treatment options in the United States. Methods: Testing was conducted at commercial locations in 3 states: New York, Pennsylvania, and Florida. Various types of Category A packaging were obtained (Fig. 1). Waste loads were comprised of Ebola patient treatment material and included personal protective equipment, sharps containers, suction canisters, drapes, and associated items. Configured packaging was placed into autoclave bins to be processed. Each package tested included a biological indicator, a class 5 integrator. Where possible, thermocouples were added to record the thermoprofile of the waste. Initially, a modified cycle was tested (a prevacuum cycle followed by exposure to steam at 138°C for 60 minutes) and a postvacuum cycle. Cycle times were adjusted based upon initial results. Results: The initial New York autoclave was tested from a cold start (no vessel preheating) resulting in a failure to obtain efficacy (Fig. 1). Successful results were no growth in recovered biological indicators, acceptable color change in integrators, and reaching and holding temperatures >121°C for 30 minutes. After making modifications to treatment cycles, which included preheating of vessels, multiple prevacuum steps and a hold time of 60 minutes, successful results were achieved in testing conducted at the treatment plants in Pennsylvania and Florida. Conclusions: Commercial autoclaves can be effective in treating Category A biohazardous waste. Each autoclave considered for treatment requires a validation process using the types of packaging containing the waste, biological indicators, integrators, and thermocouples to present a complete assessment of the treatment process.Funding: Three companies provided support for this study: Approved Storage & Waste Hauling, Daniels International, and ProMed Solutions.Disclosures: Edward Krisiunas reports contracted research for Future Health Care Systems, Daniels Sharpsmart, and ProMed Solutions.

Planning tank-truck hazardous materials shipments in intercity road transportation networks

This study proposes an integrated approach to plan tank-truck shipments of hazardous materials in intercity road networks. Considering the conventional damage and the diffusion of volatile toxicants separately, we define the risk indicators of tank-truck hazardous materials transportation. Moreover, we study the network consisting of a local distribution sub-network and a long-distance transportation sub-network. They can be implemented by a capacitated p-hub location model and a bi-level programming model. Furthermore, an exact algorithm and an improved imperialist competitive algorithm are developed to solve the bi-level programming model, respectively. Besides, there is a case study completed in a local region of East China. The numerical results demonstrate the research advantages in method innovation and engineering operation.

Risk Models for Hazardous Material Transportation Subject to Weight Variation Considerations

Reasonable risk models in hazardous material transportation are of practical significance, for safeguarding the lives and properties, protecting the natural environment, and facilitating sustainable development. The existing risk models can be classified into summation risk and maximum risk models, which result in overreliance on overall or local risk. To overcome these problems, in this article, we present two novel risk models considering different aggregation methods on local risks. The first model is supported by an ordered weighted averaging (OWA) operator, which assigns the weights according to the position of the segment risk in the process of risk aggregation, and the second model is supported by state variable weight (SVW) vector, which adjusts the weights on segments according to the change of segment risk values. Generally speaking, an OWA risk model is used under the situation with complete weighting information, whereas an SVW risk model could be used under the situation with incomplete weighting information. Based on the analysis for variable weight mechanism, we show that both models could effectively balance the overall risk with the local risks assisted by weights variety. Numerical experiments are provided to illustrate the validity of the proposed risk models.

A time-based model and GIS framework for assessing hazardous materials transportation risk in urban areas

Every day, trucks carrying hazardous materials (hazmat) in a large and densely populated city expose public health risks to the residents of the city as well as risks to the economic assets in the area. In this paper, we introduce a new risk model that considers population exposure along a route and the duration of such exposure, the latter being variable due to the congested nature of road transportation in urban areas. We have developed a spatial decision support system (SDSS) for quantitative risk analysis and the calculation of minimum-risk paths as well as their visualization on digital maps. We illustrate the usage of our proposed model and SDSS via a case study using the real road network of Istanbul, Turkey, a large metropolitan area with more than 15 million residents. We analyze Istanbul's hazmat transportation risk profile using risk analysis techniques via our interactive Geographical Information Systems (GIS)-based decision support system. We then produce a risk map of the city and run several routing scenarios between selected hazmat shipment origins and destinations. Results suggest that the hazmat routes under the new model may not always match with how hazmat is usually transported, with an economic decision-making perspective, in an urban area. Our proposed approach provides decision makers with new insights into urban hazmat transportation and is likely to reduce the consequences of incidents with large impact on public health.

A mathematical model for the diffusion of emergency warning messages during CBRNe emergencies

AbstractUnderstanding the diffusion of warning messages is essential to adequately respond to emergency events and situations. This is especially true in urgent scenarios, that is situations where external events are happening at the same rate or faster than the diffusion process itself. In this paper, an information diffusion model (Bass model) is proposed to study the spread of warning messages during emergencies involving urgent diffusion dynamics, for example a CBRNe event. In the present study, the Bass model is applied to two hazardous materials transportation accidents reported in the literature: the Pittsburgh phosphorus oxychloride release and the precautionary evacuation occurred in Confluence due to toxic chemicals released after a train derailment. Warning data collected from the two accidents and reported in published literature studies were used in this work and fitted with the Bass model. The diffusion of emergency warning messages is modelled as a two‐component system, where the spread of information is characterized by (a) a “broadcast process” that disseminates the emergency warning vertically (in the sense that many people are alerted simultaneously) and (b) a horizontal “contagion process” whereby people first hear of the event and then sequentially tell others (social media, word‐of‐mouth and peer‐to‐peer communication). The Bass model provided an excellent fit of the warning diffusion times related to both accidents suggesting that the very first phase of the warning process is sustained by a “broadcast” information diffusion process. However, after less than 1 hr from the beginning of the warning process the efficacy of its diffusion is dominated by the “contagion” component, that is the effectiveness of a robust social network between individuals. In conclusion, the Bass model proved to be a handy tool to assess epidemics spreading of information from the people who adopted the information. Our results suggest that the general Bass model applied to diffusion of emergency warning has the potential to provide key information in the management of emergencies. This approach can be applied right away by professional communicators, advisors and decision‐makers in case of a CBRNe event.

Core Competencies of Truck Drivers Responding to Emergencies during Transportation of Hazardous Materials.

Background.Hazardous material (HAZMAT) transportation drivers are responsible for safe delivery of consignments and face multiple challenges carrying out their duties. Drivers are also the first to respond to emergencies and accidents.Objectives.The purpose of the present study was to identify the essential competencies needed by HAZMAT transportation drivers to deal with emergencies.Methods.Three rounds of focus groups were conducted using expert panels comprised of HAZMAT specialists, health, safety and emergency representatives, security experts and transportation advisors from June to July 2019. The panel discussed competencies, gathered from a literature review, for emergency responders.Results.The panel identified six (6) core and 23 sub-competencies of HAZMAT drivers. This is the first study in low- and middle-income countries (LMIC) to identify core competencies of HAZMAT truck drivers.Conclusions.The integration of these competencies into a development and training program for drivers will better enable drivers to handle emergencies in an efficient and effective manner.Participant Consent.ObtainedEthics Approval.The Graduate Advisory Committee of Comsats University approved study protocols.Participant Consent.ObtainedCompeting Interests.The authors declare no competing financial interests.

The use of cultural risk assessment within the 1994 Tribal land-grant colleges and universities

In 1994, the United States Congress established 35 Colleges or Universities on Reservation Lands of the Native Americans throughout the Midwest and Western United States. These new institutions were provided annual funds from the United States Department of Agriculture for education, research and extension, components of the Land-Grant system. Today, issues related to risk assessment and risk management confront tribal decision-makers as they cope with risks, both real and perceived, that include the transportation of hazardous materials through the reservation, the clean-up of contaminated sites within the reservation, the environmental restoration of Federal facilities, the siting of waste treatment, storage, and disposal facilities, the development of tribal mineral and other natural resources, and the construction and operation of industrial and commercial facilities within the reservation. Tribal decision-makers lack Indian-specific epidemiologic, genetic, and cultural information that impact current risk assessment models needed to incorporate tribal cultural issues. There is a need to enhance the science skills of tribal college faculty in assisting tribal councils and tribal colleges in the long-term planning and stewardship of natural resources on their reservations.

Mitigating the risk of hazardous materials transportation: A hierarchical approach

Hazardous Materials (hazmat), although dangerous, are an irreplaceable aspect of everyday life. This paper is presenting an integrated traffic control policy for hazmat transportation to alleviate the risks associated with hazmat carriers. The proposed policy is devised based on dual toll pricing (DTP) and network design (ND) policies, where a two-stage simulation-based optimization framework is proposed to enhance public safety in highways. This integrated policy is devised to concurrently restrict hazmat carriers from freeways in densely populated areas via the ND policy, and control regular as well as hazmat traffic in tollways via the DTP policy. In the optimization module, mixed integer linear programming is employed to find the optimum integrated policy, where a linear-relaxation technique based on the Karush-Kuhn-Tucker (KKT) optimality conditions is applied to reduce the mathematical model. The simulation module of the proposed framework uses agent-based simulation (ABS) modeling to evaluate the suggested policies realistically. The proposed framework has been demonstrated with real traffic data of San Antonio, Texas under AnyLogic® ABS platform. The experimental results reveal that the proposed framework is able to efficiently find the optimum integrated policy which in return, effectively reduces the risk of hazmat transportation in highways.

Citizen scientists documenting hazardous materials shipments on American railroads

Economic development is powered by access to energy and industrial chemical inputs. Many of these energy forms and chemicals are harmful to human health and the environment. North American sourced petroleum crude oil has grown in volume in the past decade. Transporting this oil from its sources to refineries and export markets requires railroads. Unfortunately, there have been serious accidents involving the transportation of oil and some have questioned the conventional risk analysis used to permit its shipment by rail. At the same time climate change is being fueled by the use of hydrocarbons. A group of concerned citizens, skeptical of official information channels, began monitoring railroad rights-of-way for hazardous materials and recorded their findings. Railroad shipping data are otherwise unavailable to the general public. While energy related chemicals such as petroleum crude oil, alcohol, and butane constitute most of the observed shipments, a great deal of miscellaneous hazardous materials are present as well. Many of these hazardous materials are distributed through densely populated urban areas and ecologically sensitive places. The results of these observations are presented in this paper, followed by a discussion of the present situation and view toward future trends.

Fuzzy Random Chance-Constrained Programming Model for the Vehicle Routing Problem of Hazardous Materials Transportation

As an indispensable necessity in daily routine of citizens, hazardous materials (Hazmat) not only plays an increasingly important role, but also brings a series of transportation uncertainty phenomena, the most prominent of which is a safety problem. When it attempts to find the best vehicle route scheme that can possess the lowest risk attribute in a fuzzy random environment for a single warehouse, the influence of cost should also be taken into account. In this study, a new mathematical theory was conducted in the modeling process. To take a full consideration of uncertainty, vehicle travel distance and population density along the road segment were assumed to be fuzzy variables. Meanwhile, accident probability and vehicle speed were set to be stochastic. Furthermore, based on the assumptions, authors established three chance constrained programming models according to the uncertain theory. Model I was used to seek the achievement of minimum risk of the vehicle route scheme, using traditional risk model; the goal of Model II was to obtain the lowest total cost, including the green cost, and the main purpose of Model III was to establish a balance between cost and risk. To settle the above models, a hybrid intelligent algorithm was designed, which was a combination of genetic algorithm and fuzzy random simulation algorithm, which simultaneously proved its convergence. At last, two experiments were designed to illustrate the feasibility of the proposed models and algorithms.