Final answer:
Before caring for a patient with tuberculosis in a negative pressure room, the nurse must follow standard infection control precautions and wear appropriate personal protective equipment, including a surgical mask.
Step-by-step explanation:
Prior to caring for a patient in a negative pressure room with the medical diagnosis of tuberculosis, the nurse must follow standard infection control precautions and wear appropriate personal protective equipment (PPE). This includes wearing a surgical mask to protect against respiratory droplets that can spread the tuberculosis bacterium. Obtaining a negative pressure certification or completing a course on tuberculosis treatment may not be necessary for the nurse in this specific situation, but they should have a general understanding of tuberculosis and its treatment.