What is the first step when engaging the PTO?

Answer: B — Set the parking brake

Setting the parking brake is essential as the first step when engaging the Power Take-Off (PTO) mechanism on an aerial fire apparatus. This action ensures that the vehicle remains stationary, preventing any unintended movement that could lead to accidents or injury while performing tasks that require PTO engagement. Engaging the PTO often involves activating hydraulic systems that can cause equipment to move or operate. If the vehicle is not secured in place, there is a risk of it rolling or shifting, potentially endangering personnel or damaging equipment. By first engaging the parking brake, the driver/operator provides a stable and safe environment to proceed with subsequent checks and operations. Other pre-operation checks, such as inspecting the hydraulic system, verifying fuel levels, or inspecting hose connections, are also important but should occur after ensuring the vehicle is securely parked. These steps focus on the vehicle's readiness and safety, but initiating the process with the parking brake is critical for overall safety during operation.