What principle states that each firefighter answers to only one supervisor?

The principle that states that each firefighter answers to only one supervisor is known as Unity of Command. This principle is fundamental in emergency services and organizational management because it ensures clear lines of communication and accountability. When each firefighter reports to a single supervisor, it helps to prevent confusion regarding orders and responsibilities, allowing for more effective command and control during emergency situations.

Having a unified command structure means that all personnel understand their specific roles and where to turn for guidance, which is crucial in high-stress scenarios typical in firefighting and emergency response. Effective communication and clear leadership ultimately lead to better coordination and enhanced safety for all team members involved in the operation.

While other options, like Span of Control and Chain of Command, refer to related concepts in managing personnel and operations, they do not specifically capture the critical aspect of a firefighter answering to a single supervisor, which is central to the principle of Unity of Command.