What altitude can pilots descend to in less than 5 minutes during cabin pressurization issues?

Pilots are trained to manage cabin pressurization issues with specific altitude limits that allow for safe and rapid descent while ensuring the safety of passengers and crew. Descending to 18,000 feet is considered a critical altitude in this context, as it is approximately the threshold where a cabin pressure is typically less than that of the outside atmospheric pressure. At this altitude, passengers and crew can safely breathe without supplemental oxygen and approach a safe environment in emergencies involving cabin depressurization.

An altitude of 39,000 feet poses significant risks because the ambient pressure is much lower, and rapid decompression can lead to hypoxia, where oxygen levels are insufficient for normal function. Descending to 30,000 feet and 25,000 feet, while closer to safer thresholds, still may not provide the immediate relief necessary in a rapidly evolving pressurization emergency. Therefore, 18,000 feet is the most appropriate altitude that pilots are trained to target for a quick and safe descent to avoid health risks associated with rapid cabin altitude changes.