Before placing the apparatus in pumping mode, which control must be set?

• A. Emergency warning switch
• B. Parking brake
• C. Auto ignition switch
• D. Transmission clutch

Answer: (B)

Setting the parking brake is the essential step before putting the apparatus into pumping mode. Engaging the parking brake locks the wheels, preventing any movement as the pump engages and the engine handles increased load. This creates a stable, safe base for priming and pumping operations and helps protect crew and equipment from movement or shifting during operation. The emergency warning switch is for signaling hazards, not securing the vehicle. The auto ignition switch starts the engine, not a pre-pumping safety step. The transmission clutch controls drivetrain engagement, but immobilizing the unit with the parking brake is the standard, required precaution before pumping.