Scuba & Nitrox Glossary: Y

Nitrox and breathing-gas terminology is prioritized first. General scuba terms follow below. Definitions are educational summaries and do not replace formal training, manufacturer instructions, or an operational dive plan.

Nitrox & Gas Terms — Y

Yellow-and-Green Nitrox Marking
A commonly recognized color scheme for enriched-air cylinder identification; required markings vary by location and operator.
Yoke Oxygen Adapter
An adapter connecting compatible yoke equipment within its rated oxygen service.
Yielded Oxygen Reading
The stabilized analyzer value accepted after calibration and sampling.
Y-Mixer
A junction that combines controlled gas streams in some blending systems.
Yellow MOD Marking
A high-visibility label color sometimes used for cylinder depth identification.
Yearly Sensor Review
A scheduled evaluation of oxygen-sensor age, output, response, and replacement needs.

General Scuba Terms — Y

Y-Valve
A cylinder valve with two independently operable outlets.
Yaw
Rotation around a vertical axis.
Yoke Connector
An A-clamp regulator connection that fits over a compatible cylinder valve.
Yo-Yo Profile
Repeated ascents and descents, which can complicate buoyancy, gas use, and decompression exposure.
Vessel Yaw
Rotation around a vertical axis that changes a vessel's heading.
Yellowtail
A common name used for several schooling fish encountered at dive sites.
Yoke Dust Cap
A cap protecting a yoke regulator inlet from water and debris.
Yoke Screw
The threaded clamp mechanism securing a yoke regulator to a valve.
Young Tide
A developing tidal flow period requiring local interpretation and planning.