Is DCS possible under 20fsw, or 100% impossible?

[Raphus]

I heared about cases, where people got skin bends in a 3m pool.
Drinking alcohol the night before. Dehydrated and going up and down to fast. I spoke with the person, who claims to saw multiple skin bends of this kind.

I think(please correct me if I am wrong), that the deco models assume a normal ascent rate. Even in Ndl dives microbubbles can Form, which do no damage. But by exceeding the ascent rate and going up and down multiple times, I assume, they can become an issue.

 

[Water_is_my_blood]

Bends warning on diving in shallow water

"Dr Griffiths said that a study of 350 [DCS] cases showed at least 35 had dived in less than 10 metres of water. Those who repeatedly ascended, did hard work underwater, or drank alcohol afterwards were most at risk"

 

[huwporter]

A reasonable position might be;

If you are physiologically normal, in reasonable condition, and avoid provocative behaviours, then, for square profiles even up to the point of saturation in 20ft or less, decompression sickness is unlikely. This is supported by theory and some actual experiment.

However, in practice, you absolutely could get DCS from dives in 20ft or less, if one or more of a range of risk factors were added to the picture, including being physiologically compromised (i.e. PFO or lung shunt), exertion (either during the dive or afterwards), severe dehydration, saw tooth profiles et cetera

This is also leaving out other possible injuries such as arterial gas embolism or immersion pulmonary oedema, which are absolutely possible in less than 20ft.

(Edited to correct misuse of DCI in place of DCS)

 

[tursiops]

However, in practice, you absolutely could get DCI from dives in 20ft or less,

The question was about DCS, not DCI. It has already been established you can get DCI from a 4 ft dive, holding your breath during ascent.

 

[Water_is_my_blood]

The question was about DCS, not DCI. It has already been established you can get DCI from a 4 ft dive, holding your breath during ascent.

Bends warning on diving in shallow water

From all DCS cases (350 cases) 10% (35 cases) had dived in less than 10 metres of water. It seems possible to get bends from shallow dives.

 

[tursiops]

Bends warning on diving in shallow water

From all DCS cases (350 cases) 10% (35 cases) had dived in less than 10 metres of water. It seems possible to get bends from shallow dives.

10m is VERY different from 20 FSW.
Also bends=DCS; DCI=DCS+AGE.

 

[Water_is_my_blood]

10m is VERY different from 20 FSW.
Also bends=DCS; DCI=DCS+AGE.

"had dived in less than 10 metres of water"

20ft is less than 10m.

 

[ginti]

10m is VERY different from 20 FSW.
Also bends=DCS; DCI=DCS+AGE.

I am with you.

That article linked by @Water_is_my_blood is speaking about DCS, not DCI. However, it is speaking about 10m dives, which is 30ft... very different from the 20ft you mentioned.

The article previously posted here Is DCS possible under 20fsw, or 100% impossible?
mentioned indeed the possibility of getting bent at 10m, but stated that 20ft could be a possible limit above which DCS should not happen.

EDIT: 20ft = roughly 6m

 

[Raphus]

In the article one case is reported to be bend at 4m.which is about 12 ft.

So the answer is yes. There is at least one reported case, where this happened.

 

[Water_is_my_blood]

I am with you.

That article linked by @Water_is_my_blood is speaking about DCS, not DCI. However, it is speaking about 10m dives, which is 30ft... very different from the 20ft you mentioned.

The article previously posted here Is DCS possible under 20fsw, or 100% impossible?
mentioned indeed the possibility of getting bent at 10m, but stated that 20ft could be a possible limit above which DCS should not happen.

EDIT: 20ft = roughly 6m

It is speaking less than 10m, not 10m dives. Like Raphus wrote there is one DCS case from 4m dive.