What is indicated when the CABIN ALT caution light illuminates?

When the CABIN ALT caution light illuminates, it indicates that the cabin altitude is rising above 7,500 feet. This warning alerts the crew that the pressure inside the cabin is not being maintained at a safe level, which could lead to hypoxia if not addressed. Proper cabin pressure is crucial for passenger and crew safety, especially during flight at high altitudes.

Monitoring cabin altitude is part of the overall management of the aircraft's pressurization system. If the cabin altitude exceeds this threshold, it is vital for the crew to take action, such as descending to a lower altitude, ensuring that oxygen systems are available, or addressing any potential issues causing the cabin to lose pressure.