Final answer:
The nurse should direct the fire extinguisher towards the base of the fire and sweep from side to side. If the fire is too large or hazardous, the nurse should evacuate immediately and wait for professional firefighters.
Step-by-step explanation:
After the nurse has pulled the pin on the fire extinguisher during a fire situation, the next action should be to direct the extinguisher towards the base of the fire and sweep from side to side. This technique helps to cover the area of the fire and suppress it effectively. It is important not to spray the extinguisher in the air, as this will not reach the flames and could potentially make the situation worse. Also, making an assessment of the fire to decide whether it is manageable with an extinguisher or too large, requiring evacuation and the intervention of professional firefighters, is crucial. When using a fire extinguisher, one must always be conscious of the nearest exit, ensuring a quick escape route if the fire becomes uncontrollable. In the event that the fire is too fierce or the environment becomes hazardous, it is important to evacuate the area immediately and wait for professional help.