Diving

Question 1

The risk of decompression sickness following very deep dives can be reduced if a ___________ mixture is breathed during the dive.

Answer 1

helium-O2

Question 2

What kind of Bubbles are formed that lead to Decompression sickness? And what is it called if the bubbles form in joints causing pain or neurological disturbances?

Answer 2

Caused by the formation of N2 bubbles during ascent from a deep dive.

May result in pain (“bends”) and neurological disturbances.

Can be prevented by a slow, staged ascent.

Treated by re-compression in a chamber.

Incidence is reduced by breathing a helium-oxygen mixture.

Question 3

Commercial divers who are working at great depths, for example, on pipelines, sometimes use ___________________. When they are not in the water, they live in a high-pressure chamber on the supply ship for several days, which means that they do not return to normal atmospheric pressure during this time. In this way, they avoid decompression sickness. However, at the end of the period at high pressure, they may take many days to decompress safely.

Answer 3

Saturation diving

Question 4

Inert Gas Narcosis typically occurs a depths below?

Answer 4

Although we usually think of N2 as a physiological inert gas, at high partial pressures, it affects the CNS. At a depth of about 50 m (160 ft), there is a feeling of euphoria (not unlike that following a glass or two of alcohol), and scuba divers have been known to offer their mouthpieces to fish! At higher partial pressures, loss of coordination and eventually coma may develop. Other gases, such as helium and hydrogen, can be used at much greater depths without narcotic effects.