What must be done if the cabin pressure exceeds 6.0 psi?

If the cabin pressure exceeds 6.0 psi, the appropriate action is to descend to a lower altitude immediately. This response is crucial because exceeding the recommended cabin pressure limit can indicate a potential cabin pressurization failure, which could jeopardize the safety of the passengers and crew.

Descending to a lower altitude helps to normalize cabin pressure and reduce the risk of hypoxia or other pressure-related complications for those on board. The human body requires a certain level of atmospheric pressure to function correctly, and when this threshold is exceeded, immediate corrective action is necessary to maintain safety.

Other options, such as continuing normal operations or climbing to a higher altitude, would not address the underlying issue and could pose significant risks. Performing an emergency landing may be a necessary step if the situation is severe, but the primary immediate action is to descend to alleviate the excessive pressure.