A hazardous material (or hazmat for short) is defined as any substance or material capable of causing harm to people, property, or the environment (U.S. Department of Transportation [U.S. DOT]). Some

4.1 Hazardous Materials: Definition and Classification 77 4.2 The Cause, Significance, and Mode of Hazmat Shipments 79 4.3 Hazmat Shipment Accidents: Causes, Consequences, and

Probability of Occurrence 79 4.4 Multiple Parties and Multiple Objective Hazmat Shipment 84 4.5 Risk Management 85

4.5.1 Regulations 85 4.5.2 Compliance 86 4.5.3 Exemptions 86 4.5.4 Mitigation 86 4.5.5 Risk Management Self-Evaluation Framework 87

4.6 Risk Assessment 87 4.7 Routing 90

4.7.1 Optimization Techniques for Hazmat Routing Problems 92 Shortest Path Models 92 Vehicle Routing Problem Models 94

4.8 Combined Hazmat Facility Location and Routing Problem 95 4.9 Concluding Remarks 96 References 96

daily life examples include gasoline and diesel. Indeed, there are many hazmats in reality. They are classified into nine categories according to their physical, chemical, and nuclear properties (Keller and Associates 2001). Table 4.1 depicts the nine categories in detail. As we can see from this table, hazmats can be explosive, flammable, oxidizing, toxic, radioactive, or corrosive.