Fairness in hazmat routing-scheduling: A bi-objective Stackelberg game

•A hazmat routing-scheduling problem is formulated as a bi-objective game.•A FIFO discipline is applied to waiting places to keep fairness among dispatchers.•Risk and travel time objectives are included to embed the planner’s risk attitude.•By solving the problem with a modified ALNS on a real case, insights are presented. We investigate a hazmat routing-scheduling problem. To minimize the overall expected risk, various vehicles may take different routes/schedules to avoid multiple accidents on the same link. Therefore, the company envisages two issues: (1) unfairly, a vehicle departing earlier from its origin may arrive earlier at its destination than the others leaving later; (2) focusing only on the minimization of risk may increase travel time/cost incurred by the company. We suggest a bi-objective game-theoretic formulation and solve it by a modified Adaptive Large Neighborhood Search and Simulated Annealing. We test the solution on a real-life case and extract practical insights.