What is a characteristic of 'Paid-on-call' staffing?

'Paid-on-call' staffing is a system where firefighters are compensated specifically for their responses to calls. This means that members of a fire department operating under this model only receive payment when they actively respond to emergencies or participate in certain training events. This compensation structure allows fire departments to maintain a level of staffing without the continuous financial burden of a full-time workforce.

The other options do not accurately represent the 'Paid-on-call' staffing model. Specifically, members being unpaid or volunteering their time would not align with the concept of 'Paid-on-call,' as this type of staffing inherently involves some level of financial compensation tied to their responses. Similarly, receiving a salary implies a steady, continuous payment schedule, which contradicts the episodic compensation nature of 'Paid-on-call' positions. Thus, the correct choice clearly identifies the essence of this staffing arrangement.