How long must an ACM wait to fly after scuba diving?

An aviation crew member, or ACM, is required to wait 24 hours after scuba diving before flying due to the risk of decompression sickness, commonly known as "the bends." During scuba diving, a diver can absorb nitrogen at higher pressures, and as they ascend, nitrogen is released from the body. If a diver ascends too quickly or does not allow sufficient time for the nitrogen to be safely eliminated, it can lead to serious health issues when exposed to the lower pressure in the atmosphere at flight altitudes.

The 24-hour waiting period is a guideline recommended by various aviation and diving organizations to ensure that all residual nitrogen has been appropriately processed by the body, reducing the risk of complications while in flight. This timeframe is dedicated to allowing the body's decompression to occur safely, protecting the diver's health and ensuring safety during flying operations.

Other suggested waiting periods such as 12, 48, or 72 hours are not standard for routine scenarios. The established 24-hour guideline balances safety and practicality for aviation crew operations.