Scuba fatalities - Los Angeles County - 1994-2007

[Ken Kurtis]

I saw Lt. John Kades at the L.A. County Coroner's Office last night. (He's a diver, BTW, as is Chief Investigator Craig Harvey - two of the reasons why we try to do a really throough job i slooking into these accidents that haopopen within the jurisdiction of the Coroner's Office.) I got from John the accident statistics I mentioned yesterday. These are the same numbers that we presented at our "Why Divers Die" seminar at the Scuba Show on June 21.

The caveat from Lt. Kades is that for 2000-2007 we have a high degree of confidence in the numbers. In others words, we're pretty sure they represent all the fatalities in that time frame. For 1994-1999, we have good info on the ones that we have, but it's possible that we're missing others. (This was beofre Kades was involved with the Coroner's Office.) And before 1994, we're still working on getting good data.

Don't lose sight of the fact that small numbers and small sample sizes can easily be skewed by one more or one fewer. (For instance, 2004 was not 40% safer than 2003, and 2005 was not 66% more dangerous than 2004.) Longer-time trends will be more representative than shorter-term ones. With that in mind, here's what we've got:

1994-2007 (14 years) - 53 fataltiies (avg 3.8/yr)
1994-1999 (6 years) - 21 fatalties (avg 3.5/yr)
2000-2007 (8 years) - 32 fatalities (avg 4.0/yr)

Of the 53:
• 81% male, 19% female
• Average age 38.4 yrs old (oldest - 60, youngest - 14)
• 37.7% due to a medical component

Of the 53, by the numbers:
• 19 (35%) were from charter boats
• 11 (20%) were at Casino Point
• 3 (5%) were of natural causes
• 3 (5%) had alcohol/drugs as a factor
• 2 (3%) casue of death was undetermined
• 2 (3%) were skin divers (shallow-water blackout I think)
• 2 (3%) were on rebreathers
• 1 (>1%) was a commercial diver

Of the 53, by year:
• 1994 - 5 fatalities
• 1995 - 5 fatalities
• 1996 - 4 fatalities
• 1997 - 2 fatalities
• 1998 - 4 fatalities
• 1999 - 1 fatalities
• 2000 - 4 fatalities
• 2001 - 3 fatalities
• 2002 - 3 fatalities
• 2003 - 5 fatalities
• 2004 - 3 fatalities
• 2005 - 5 fatalities
• 2006 - 6 fatalities
• 2007 - 3 fatalities

So there you have it. What does all of this mean??? Ahhhh, that's the $64,000 question. And hopefully we'll get some robust discussion going on that thought. (My suggestion would be that every now and then a shift in discussion theme merits a new thread.)

Hope this helps or at least gets you thinking.

 

[Teamcasa]

Thanks for the data Ken.
One other factor is needed to really determine if diving is getting more dangerous. That is the total number of divers in a given year. For me I do think diving is getting more popular as many baby boomers can now afford the added time and money for recreation. With this, another factor in the data is needed. How many of the newly certified divers were in a +50 age group?

One way or the other, I think diving is safer now than it ever has been.

 

[selo]

Ken, thanks for the data. Following on Teamcasa's suggestion, it would be very useful to get some idea of the number of divers over time. Even more useful would be the number of total dives (=number of divers times average dives per diver). Then we could calculate fatalities per dive.
We could try to get the number of certified divers from the major agencies. I am not sure how to get the average dives per diver figure. From the sales of equipment perhaps?
What do you think?

 

[swamp diver]

Thanks for posting the data. Two questions come to mind.

1) In what percentage of the fatalities was a blood carboxyhemoglobin level done?
2) In what percentage of the fatalities was a tank air/gas analysis done?

Are you able to breakdown the medical component into obesity (BMI>30), hypertension, smoker, or diabetes to give a better idea of the risk factors at play.

 

[Ken Kurtis]

1) In what percentage of the fatalities was a blood carboxyhemoglobin level done?

I don't know. I'll ask the Coroner but may not get an answer right away.

2) In what percentage of the fatalities was a tank air/gas analysis done?

100% for all the ones I've done (since about 2004). Now I will tell you that what we do is simly an oxygen analysis. We don't look specifically for CO or do a full-sprectrum analysis unless the oxygen level is off or if we have some other evidence to consider the air may have been a culprit. (Other people getting sick, for instance.)

We did have one tank that we analyzed years ago where the oxygen level was 14%. It was not a tri-mix. We sent it over to AQMD for a full spectrum analysis and what came back was essentially 14% oxygen and 85% nitrogen (plus miniscule inert gases) but what was most interesting was the absence of any CO in the mix. AQMD said that that meant it was a blended mix, not just off a compressor (which will pick up some CO in the air).

In this case, the diver had gone (solo) to a depth in excess of 200 feet, started back up, and passed out at around 100 feet. The PPO2, even with a 14% mix, should not have caused the passing out (there was still signficiant gas in the tank) so that part remained a mystery. Due to some other details that I won't reveal here, there was some speculation that it may have been suicide but there wasn't enough evidence to state that firmly. So sometimes you just don't know.

But back to your orginal question: the air is tested in every fatality in L.A. County and if anything looks out of whack, further tests are done. I can't speak for other jurisdictions.

 

[TSandM]

So, if 37% involved a medical problem, that means that 63% did not. Any analysis as to commonalities in the non-medical deaths? (Eg. buoyancy control problems, running out of gas, etc.)

 

[vladimir]

Of the 53:
• 81% male, 19% female
• Average age 38.4 yrs old (oldest - 60, youngest - 14)
• 37.7% due to a medical component
Of the 53, by the numbers:
• 19 (35%) were from charter boats
• 11 (20%) were at Casino Point
• 3 (5%) were of natural causes
• 3 (5%) had alcohol/drugs as a factor
• 2 (3%) casue of death was undetermined
• 2 (3%) were skin divers (shallow-water blackout I think)
• 2 (3%) were on rebreathers
• 1 (>1%) was a commercial diver

What is the distinction between the 37.7% due to medical component and the 5% due to natural causes?

 

[Ken Kurtis]

What is the distinction between the 37.7% due to medical component and the 5% due to natural causes?

My understanding is that that 37.7% would be things like undiagnosed heart disease (that's a biggee) or other medical issues that might not be a big deak when you were walking around at 1ATM but which were exaccerbated by the physical demands scuba diving puts on your body.

The 5% natural are people whose time had come and they coincidentally happened to be diving. There was one guy who had massive organ failrure during his dive. It could just have easily happened while he was sitting in his car.

Obviously, a lot of this is dependent on how the doctor interprets things. Personally, I'd tend to lump the medical and natural together as "not diver error."

It's the 57.3% diver error (diving after surgery, not turning on air, turning off rebreather electronics, trying to retrieve a weightbelt at night with less than 500psi in your tank, etc., etc.) that we should be able to eliminate just by diving smarter.

 

[Kevrumbo]

Some Stats to add to this Thread
(Boldface emphasis added by myself):

Initial Reported or Observed Problem of Divers Brought to the Catalina Hyperbaric Chamber (1995 - 2000):

No Problems Noted: approx. 10% occurrence
Buoyancy Problem: 12%
Air Supply Problem: 11%
Buddy Problems: 10%
Decompression Problem: 6%
Equalizing Problem: 6%
Pain: 6%
Uncomfortable: 5%
Environmental Problem: 4%
Equipment Problem: 3%
Medical Problem: 3%
Regulator Problem: 3%
Rapid Ascent: 2%
Fatigue: 2%
Rebreather Problem: 2%
Mask Problem: 2%
Aspiration (water): 1%
Panic: 1%


Divers Brought to the Catalina Chamber
--Did They Panic During the Dive?
Panicked: 33%
Did not Panic: 42%
Unknown: 25%


Divers Brought to the Catalina Chamber
Suffering From AGE/Drowning/Near Drowning
--Did They Panic During the Dive?
Panicked: 51%
Did not Panic: 19%
Unknown: 30%


Cases from 1995 thru 2000
Of 154 Divers Brought to the Chamber:
76 (49%) Recompressed:
43 (57%) of which were DCS related
33 (43%) of which were Air Embolism related

78 (51%) Not Recompressed:
23 (29%) Rule Out AGE
23 (29%) Rule Out DCS
19 (24%) Near Drowning
9 (12%) Drowning
4 (5%) AGE/DCS Refused Treatment Against Medical Advice

19 (12%) Full Arrest --Fatalities

 

[vladimir]

Thanks, Ken, that makes sense.