Safe solo freediving?

[crowplus]

Have been snorkling solo in Pacific NW solo for 6+ years.
Dive profile is generally not deeper than 20ft (visibility)for under a minute. Is that considered Freediving? Is SWB risk present.

Have felt reasonably safe because positive buoyancy of wetsuit/weights. Now wonder.

First became aware of SWB through various Freediving links.
Not sure it applies to my profile.

Is there a rule of thumb for depth and time that precludes SWB?
Thanks.

[Bill]

Originally posted by crowplus
.....
Dive profile is generally not deeper than 20ft (visability)for under a minute. Is that considered Freediving? Is SWB risk present....

In a word, yes. There are lots of cases in less than 10 feet.
If you don't follow the advice you're going to get, at least leave you're watch at home. I don't know if it will reduce the risk or not but, every swimming pool death seems to involve a watch.

[Angus]

According to Terry Maas freediving is snorkling beyond -15 feet in depth. Why 15 feet is the limit is a mystery that I have never had satisfactorily answered. (Anyone know the reason for this depth boundary?) The possibility of SWB is remote at this depth but that is the big and trendy issue whenever we talk of freediving even though most of us will never experience it or witness it.

There are far more mundane dangerous that can kill us when we are solo freediving such as cramps, boats, currents, hypothermia, or entanglements. These prosaic issues are seldom discussed yet account for far more deaths than SWB. I dive alone and am far more concerned with these factors than SWB. I think about them, plan for them, and adjust my dive and location as a result. SWB is a much bigger concern in spearfishing when we become focused on the hunt and lose track of time and depth or when we are competing, for the same reasons.

[SASpearo]

Hi all,

I think the 15 ft threshold has to do with breathhold lung capacity. When diving to 5 metres (15 ft) one's lung capacity halves because of the water pressure. Interestingly enough, one has to get down another 12 metres for it to halve again ... so it's exponential ....

In other words, if you start at the surface with a 8 litre lung capacity, you will only have 4 litres worth at 5 metres ...... check your dive buddy's rib cage out next time you dive (without suits) ... it gets pretty scary at around 25 metres ....

[Erik]

To clarify...at 10 metres, the volume is reduced to half, at 20 metres, 1/3 , and at 30 metres, your lungs are 1/4 their original size. The rib cage will compress to a point, but blood shift will take over after a depth that is variable depending on the diver's physiology and other factors.
Cheers,
Erik Y.

[SASpearo]

Sorry 'bout that ..... got my feet and metres mixed up a little - I'm from sunny South Africa and we use Metres .......

Thanks 4 de clarification !