An Open Letter of Personal Perspective to the Diving Industry by NetDoc

[boulderjohn]

I weigh 220 pounds.

In fresh water with my dry suit, medium underwear, a steel Back plate, and a single aluminum tank, I use 16 pounds of lead.

In fresh water with my dry suit, medium underwear, a Hollis harness, and two Worthington steel 85 tanks mounted sidemount, I don't need any weight.

In fresh water with my dry suit, medium underwear, a steel backplate, and steel double 108s mounted backmount, I don't need any weight.

 

[Zippsy]

Also, the Sheriff's report indicates it's a 5 mil, not a 7. Which is right?

Without a caliper and access to the suit, I think the answer to that question depends on whether or not we believe he was over weighted.

---------- Post added January 3rd, 2015 at 09:26 AM ----------

I am 6 ft 240lbs ( need to lose the weight again)

I weigh 220 pounds.

I'm 6'11", 295 pounds and I can't understand why people argue with me.

 

[redacted]

Where did this information come from? The testimony of the guy who found the body indicates that he had to remove all of the gear to get the body off of the bottom. I'll have to go find it again and reread it to be sure. I certainly don't remember this testimony from him.

You missed the point. Neoprene is filled with voids and rubber. If it were a perfect balloon (no neoprene) then it would be a twenty percent increase. But there's a lot of neoprene in there giving the suit weight and structure. The less rubber, the more floaty the material and greater the compression with depth. Also, the Sheriff's report indicates it's a 5 mil, not a 7. Which is right?

The condition of the body and the thermal protection were both in Dr.S's statement.

Old discussion about the compression of neoprene:
Data on Neoprene compression at depths? [Archive] - ScubaBoard - Scuba Diving Forum - Diving Social Network

Granted, as neoprene becomes more compressed, it should start to behave more like a rigid mass than a stretchable one. But, initially, its behavior seems to be more balloon like than steel tank like. I don't think my estimate is far off.

When physics and testimony conflicts, I lean towards the physics but don't fully trust either. I expect to work to understand the conflict. It is not that I don't trust the theory, I just know that folks can get it wrong in practice. Not unlike statistics.

 

[boulderjohn]

Without a caliper and access to the suit....

When I dived in the Galapagos, I had to make a decision about what wet suit to bring because we heard there would be a fairly significant difference in temperature between the islands. We heard that there would be 7mm suits on board for rental, so I decided to bring my 5mm suit and rent a 7mm if it was not enough. At that time my 5mm suit was a unique design by ScubaPro that they only sold in the 5mm size. Imagine my surprise when I saw the 7mm suits on the boat and saw that they were the same ScubaPro model I had brought with me. What they said were 7mm suits were clearly 5mm suits.

---------- Post added January 2nd, 2015 at 05:54 PM ----------

I Googled weighting guidelines and found a lot of sites. Here is what I found:

According to the PADI eLearning guidelines, in salt water with a 7mm suit, the diver should have 15-17 pounds, and 11-13 pounds in fresh water.

According to the calculator used by this dive shop, with a two piece 7mm suit and a steel tank, he should have had 11-13 pounds.

According to this site, with a two piece 7mm suit and a steel tank, he should have had 11 pounds.

These guidelines would have him in the 11-13 pound range with a two piece 7mm suit and a steel tank.

This calculator got him all the way up to 14 pounds with a two piece 7mm suit and a steel tank.​

Summary: The highest weight estimate I found for a 120 pound diver with a two piece 7mm suit and a steel tank was 14 pounds. It seems to me that 30 pounds is a tad high.

 

[The Chairman]

The condition of the body and the thermal protection were both in Dr.S's statement.

So, not from the eye witness account but from a bought and paid for 'expert witness'. I think I believe the eye witness over Dr S.

But, initially, its behavior seems to be more balloon like than steel tank like. I don't think my estimate is far off.

Have a look see:

This is why I own WetWear suits! They are awesome, they keep me warm and they are very, very stable.
​

 

[dmoore19]

If it matters, I am not sure where the Boy Scouts would be doing these dives. What I do know is that I have spent quite a bit of time on Bear Lake boating and water sports, not scuba however.

Bear lake is a quite pretty turquoise blue in color. The swim beach and recreational area has a very sandy bottom, not silty at all. Not saying where the dives occur had similar conditions but that is an honest representation of the water and the bottom of Bear Lake as I know it.

 

[redacted]

So, not from the eye witness account but from a bought and paid for 'expert witness'. I think I believe the eye witness over Dr S.

Have a look see:

This is why I own WetWear suits! They are awesome, they keep me warm and they are very, very stable.
​

I agree on the leaning of Dr. S's statement - it sure looks to be designed as a defense for the instructor. But he does do a fairly good job of documenting specific sources many of whom were involved in the incident. Can you provide any of the eye witness statements?

And, yes, not all neoprene is the same. But, if you want stretch, you pretty much have to accept more compression. The rental fleet is unlikely to be Rubatex.

 

[Storker]

Since I'm neither an MD with specialization in diving medicine, nor a multi-certified diving instructor, I'd like to know if anyone could answer a few questions I have after reading Dr. Sawatzky's report:

Drowning simply refers to someone who dies while in the water

How does this statement from an apparently well-credentialed diving doctor fit with WHO's current definition of drowning (van Beeck et al., Bulletin of the World Health Organization, 83(11), 2005, 853-856)?

Drowning is the process of experiencing respiratory impairment from submersion/immersion in liquid

he was correctly weighted.

Is it really possible to state that with such certainty? If so, can I ask him to calculate all my weigthing needs down to the nearest lb, in any gear config?

the water in Bear Lake is [...] denser than the ocean

Isn't that a pretty strong statement, considering that I can't find any density figures in the report? How much denser is Bear Lake water than ocean water?

He almost certainly lost consciousness after ascending slowly from a depth of approximately 15 feet to near the surface as a result of pulmonary barotrauma and arterial gas embolism. This cannot be proven to a one hundred percent degree of certainty as the autopsy performed on David did not follow the special procedures required in divers who die while diving

Is it acceptable for a trained medical doctor to base a conclusion as strong as this only on pure theoretical considerations and a lack of evidence for a contrary conclusion?

 

[The Chairman]

Storker, I'm sure he's the best money can buy. There's a lot of money being made in this law suit. I don't know what these guys charge an hour, but I bet it's top dollar. I don't think I could ever be an expert witness and charge for it. It's reasonable to cover expenses, but that's about it.

 

[cerich]

Storker, I'm sure he's the best money can buy. There's a lot of money being made in this law suit. I don't know what these guys charge an hour, but I bet it's top dollar. I don't think I could ever be an expert witness and charge for it. It's reasonable to cover expenses, but that's about it.

for Dr. Sawatzy it is in his report, he charges $250 a hour usd.