Definition
Scuba diving conducted within depth and time limits that allow the diver to ascend directly to the surface without being required to make scheduled in-water decompression stops. Even after such diving, dissolved nitrogen remains in the body tissues and can come out of solution as bubbles if the diver is exposed to reduced atmospheric pressure too soon, such as by flying shortly after the dive.
Plain English
Diving that stays shallow enough or short enough that the diver can come straight back up without having to pause underwater to let absorbed gas work its way out safely.
Context Anchor
Seen in FAA guidance on how long a pilot or passenger should wait before flying after scuba diving.
Derivation
‘Decompression’ comes from Latin de- (reverse) and compressus (pressed together) — literally ‘un-pressing.’ Underwater, the diver’s body is pressed by water pressure and absorbs extra nitrogen. ‘Nondecompression stop’ means the diver does not need to pause during the ascent to let that pressure release in a controlled way.
Why Pilots Care
Determines the minimum surface interval required before flight to prevent decompression sickness at altitude.
Analogy
It is like driving a route that does not require scheduled rest stops: you may still choose to pause, but the route does not require it.
Grounding Statement
The key idea is that the diver surfaced normally without required waiting stops, but flying too soon can still increase the risk of pressure-related illness.
Intuition Check
Do not read “nondecompression stop” as “no stopping is allowed.” It means no decompression stop is required; an optional safety pause may still happen.
Example Sentence 1
After a morning of nondecompression stop diving, the pilot waited the full 12 hours before departing on the afternoon flight.
Example Sentence 2
Nondecompression stop diving still requires waiting the recommended surface interval before any exposure to reduced cabin pressure.