Optimal routing for infectious waste collection

Most Small to medium-sized hospitals and clinics in Taiwan do not have on-s ite treatment facilities for their medical and infectious wastes and must r ely on outside agencies for its collection and treatment. The problem of op timally planning and scheduling the collection of medical wastes from a dis perse group of facilities is formulated as a periodic vehicle routing probl em. Special attention is paid to the requirement that waste pickup be made on at least a weekly basis. A two-phased approach is used to solve the resu lting optimization model. The first phase solves a standard vehicle routing problem to determine a set of individual routes for the collection vehicle s. The second phase uses mixed-integer programming to assign routes to part icular days of the week. An illustrative example for 38 hospitals in the Ta ipei city area demonstrates the effectiveness of the approach.