////Underwater Breathing Apparatus
Underwater Breathing Apparatus 2017-07-31T15:15:18+00:00

Underwater Breathing Apparatus

Underwater Breathing Apparatus Sounds

 

“Traditional” scuba systems include a steel or aluminum alloy cylinder of compressed air attached to a two-stage “demand regulator”. These systems produce underwater noise associated with the bubbles that are produced when the diver exhales, as well as when s/he inhales and air flows through the regulator valve. Image credit: Shay Viehman, NOAA.

 

Description

Divers use underwater breathing systems for recreational, scientific, commercial, and military purposes. There are three types of self-contained underwater breathing apparatus (SCUBA): “traditional” steel or aluminum alloy cylinder of compressed air, semi-enclosed circuit re-breathers (SECRs), and fully closed circuit re-breather systems (CCRs). The traditional SCUBA systems use a two-stage “demand regulator” to reduce the air pressure in the cylinder to the external pressure for the diver to inhale. With these systems, when the diver exhales, bubbles are released into the surrounding water. Semi and fully closed rebreather systems produce few or no bubbles.Traditional SCUBA systems generate low frequency sounds associated with the gas bubbles they release. SCUBA bubbles produce low energy noise in the frequency range of approximately 100 to 400 Hz. Periodic bursts of sound (1.3-5 kHz) also occur as a diver inhales and air flows through the regulator.

References

Cole, R. G., Syms, C., Davey, N. K., Gust, N., Notman, P., Stewart, R., Radford, C. A., et al. (2006). “Does breathing apparatus affect fish counts and observations? A comparison at three New Zealand fished and protected areas,” Marine Biology, 150, 1379–1395. doi: 101007/s00227-006-0420-3
Lobel, P. S. (2001). “Fish Bioacoustics and Behavior: Passive Acoustic Detection and the Application of a Closed-Circuit Rebreather for Field Study,” Marine Technology Society Journal, 35, 19–28. doi: 104031/002533201788001884
Radford, C. A., Jeffs, A. G., Tindle, C. T., Cole, R. G., and Montgomery, J. C. (2005). “Bubbled waters: The noise generated by underwater breathing apparatus,” Marine and Freshwater Behaviour and Physiology, 38, 259–267. doi: 101080/10236240500333908