Which of the following is included in the seven pump certification tests required by NFPA 1901?

The engine speed check is one of the seven pump certification tests required by NFPA 1901 because it ensures that the fire pump operates at the manufacturer's specified RPM under load conditions. Proper engine speed is crucial for maintaining adequate water pressure and flow rate, which are vital for effective fire suppression. This test verifies that the engine is functioning optimally and that the pump can perform its intended duties during emergencies.

In contrast, the other options do not fall under the scope of the NFPA 1901 requirements. For example, while a visual inspection is an important part of maintenance protocols, it is not one of the formal certification tests outlined in NFPA 1901. Fuel efficiency tests are typically associated with the overall performance of the apparatus but are not a specific requirement of the pump certification. Similarly, the pump voltage test may be relevant for electrical safety checks but is not mandated as part of the pump certification process.