What should you advise a passenger suffering from a nosebleed to do?

Advising a passenger suffering from a nosebleed to sit forward and pinch their nostrils for at least five minutes is the recommended first aid approach. This position helps minimize the risk of blood flowing down the throat, which can potentially lead to choking or nausea. By leaning forward, the blood is directed forward, allowing it to exit the nostrils rather than being swallowed.

Pinching the nostrils helps apply pressure to the bleeding site, which can assist in stopping the hemorrhage. Maintaining this pressure for a sustained period, typically around five to ten minutes, gives the blood vessels time to constrict and seal the wound, thereby controlling the bleeding effectively.

Other methods, such as leaning back, are not advised because they increase the likelihood of swallowing blood, which can be harmful. Applying ice to the back of the neck does not specifically address the site of the bleeding and is not as effective as direct pressure to the nose. Laying down flat and elevating the head can be counterproductive by encouraging blood to flow backward towards the throat. Thus, sitting forward and applying pressure to the nostrils represents the most effective and safe technique for managing a nosebleed.