Several factors should be considered when selecting circuit breakers, including the electrical characteristics of the circuit (voltage, current, frequency), the type of load being protected (resistive, inductive, capacitive), the ambient environmental conditions (temperature, humidity), the required interrupting capacity, and compliance with relevant industry standards and regulations (such as UL, IEC, NEC). Additionally, considerations such as installation space, maintenance requirements, and cost-effectiveness play a role in choosing the most suitable circuit protection solution for a particular application.