texascavers Digest 14 Jun 2010 06:56:06 -0000 Issue 1080
Topics (messages 15112 through 15120):
Re: carbide vs LED (attempt 2)
15112 by: Bill Walden
15113 by: Chris Vreeland
15114 by: Don Cooper
Carbon Dioxide and Low Oxygen in Texas Caves.
15115 by: SS
15119 by: JerryAtkin.aol.com
more new LED stuff
15116 by: David
a cave question
15117 by: David
15120 by: JerryAtkin.aol.com
caver music ?
15118 by: David
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----------------------------------------------------------------------
--- Begin Message ---
While surveying a cave in southern Kentucky years ago, well decades ago, I
developed a headache. After a few more shots down and into a room with a huge
pile of rotting leaves, my carbide lamp started acting up. For some reason I
climbed up high and onto a ledge to change carbide. The lamp still had plenty
of good carbide. I looked down at my companion and noted he was fumbling with
his carbide lamp and not accomplishing anything. At that point I realized what
was wrong and shouted at my companion to climb up where I sat. Once he climbed
up to my level his carbide lamp started to burn properly. We beat a hasty
retreat. My headache went away once we were outside the cave.
That same year I remember survey trip to another cave. We had a high school
student with us, who was a student of the 3rd member of the team. The student,
Paul, had a brand new waterproof pack. As we were preparing to leave for the
day, Paul decided to change carbide. We were next to the cave stream. As Paul
opened his pack there was a tremendous explosion. The blast burned all the hair
off Paul's face and his face was bright red with black soot. We washed his face
as quickly as we could with the cold stream water. He complained of pain from
the burn. By the time we got to town Paul didn't feel the need to visit a
doctor or require any pain ointment. The red color had pretty much gone away.
By morning he was fine albeit minus facial hair.
When I first started caving, one could buy carbide at a local hardware store,
either in bulk or in a can. I bought a 100 pound drum of carbide which I shared
with fellow cavers.
I've had two Princeton Tec LED lights go bad - an Apex and an EOS. Princeton
Tec replaced both under warranty without question. If you get the Princeton Tec
lights wet inside, just open them up to get the excess water out and re-close.
Once home or back at camp, open the lamp up and allow the circuit board to dry.
For about ten years I was building my own LED head lamps for caving. I made no
attempt to waterproof the lamp or electronics other than a conformal coating on
the circuit board. The LED element was mounted on a home made aluminum bracket
(bolted to the helmet) that doubled as a heat sink. The circuit board was
mounted to the back side of the bracket. The fixture was submerged many times
and was never affected by being wet. The typical arrangement consisted of one
Luxeon 1-watt LED and four super bright 1/8" LEDs all mounted on the aluminum
bracket. (Very much like the Apex arrangement.) Other than having to replace
the switches, I never had any problem with those head lamps. I considered them
a big improvement over the Nite Lite that I previously used and definitely an
improvement over a carbide light. I continued to carry my trusty Autolite for
backup and for placing survey stations. I never had to use it as a backup and I
eventually started using either a Sharpie or red fingernail paint to mark
stations with a very small dot. I haven't carried a carbide lamp for years now.
I was lucky to work for a company that permitted and encouraged employees to
work on personal projects during their lunch hour and outside of working hours
and allowed them to take parts from "open stock" without charge. Parts taken
from "controlled stock" had to be signed out and judgment used as whether or
not to reimburse the company. Our quality assurance manager was always happy to
make custom circuit boards for employees. (I think that he had too much free
time available.)
My best to all,
Bill Walden
----- Original Message -----
From: Philip L Moss
To: [email protected]
Sent: Sunday, June 13, 2010 9:20 AM
Subject: Re: [Texascavers] carbide vs LED (attempt 2)
Mark Alman wrote:
"Wow, after reading all of these near-death incidents caused by or around
carbide, it makes me wonder why anyone would consider not switching to 100% LED
use!
Mark
Well, I could quibble about whether or not carbide caused all the incidents
or whether the propane leak might have been a cause.
An accident is what happens when the immutable laws of physics are ignored. -
Ambrose Bierce
But what about all the deaths carbide lights have prevented? I can think of
a few trips personally where the carbide lamps were the only indication of high
CO2/low O2. More than once I have rappelled into bad air and knew almost
immediately by the response of my carbide lamp. The most recent time was less
than a year ago. No LED light will tell you that. For those of you who don't
have much experience with low O2 in caves, it can be highly stratified in
caves. I have had my head in 15% 02 while at my feet it was 9% (I had a meter
that day). OSHA forbids working in atmospheres below 18% O2, if memory serves.
At 9%, one passes out very quickly. Imagine you are rappelling into a
stratified atmosphere similar to this one. How slowly are you rapelling and
how are you going to notice the changes in air quality? Changing over on rope
in bad air is very difficult in my experience even if the air quality is
significantly better than 9% O2; low O2 makes one stupid (temporarily, I am led
to believe).
Cap lamps mark stations well with removable, relatively benign marks and will
mark on relatively wet surfaces.
A cap lamp can be made completely nonmagnetic, is easily removable so that
one can read instruments without having yet another piece of equipment to bring
into the cave.
They work and are durable. I have used a cap lamp since I started caving in
1971. I have tried electrics over the years from time to time and currently
own an Apex. I still have yet to find one I trust to last. My Apex leaks if I
put under water and sooner or later it will corrode and quit working from that
or some other reason that I will fail to understand. I have dropped a cap lamp
down a 90 foot pit; it had a minor ding and I was able to continue using it for
many more years and still have it in working order. The Autolite I am using is
probably more than 50 years old. With very low tech maintenance, there is
nothing that will go wrong with it that I cannot fix without tools in the cave.
And it will probably go another 50 years with a reasonable amount of care
(which is more than I can say for me).
Do you think that any of the individual lights in use today will still
useable in 20 years? And if not, what does this say for the likelihood that
they will fail while you are depending on them? How many times have you been
on a trip where an electric light has completely failed? I have seen it
frequently. So far, I have not seen a Stenlight fail, but I have seen several
Apex fail and high number of Petzel products. But Stenlights, while very
bright are also very magnetic and pretty expensive.
Carbides are still not very good for diving I will grant, but with a little
knowledge, they stand up to long-term immersion quite well. I will also grant
they have real drawbacks on multi-day in cave camps. And there is a learning
curve that appears to be a bit much for some people. And the USDOT has made it
relatively expensive to buy carbide.
However, I no longer encourage new people to use carbide lamps. I do think
that a durable enough LED light for a reasonable price is not far off. But I
think there are some real advantages in having some of us around (OK, so I am
not around you in particular) who still know and use the old technologies. And
most of us don't bring CO2 meters caving.
Philip L. Moss
[email protected]
PS If any of you know why my emails occasionally look like Chinese characters
when I use the reply function and can tell me how to prevent the font switch
without the simple expedient of never using reply, I would appreciate the
advice off line.
____________________________________________________________
Six Sigma Certification
Villanova Six Sigma Certification 100% Online Program - Free Info.
VillanovaU.com
--- End Message ---
--- Begin Message ---
The only time I ever rappelled into Deadman's hole, I had an
experience like this. I went down slowly, expecting possible co2
because the caves in the Ellenberger in that area are known for it,
but still, I was very surprised by how stratified it was. Where I
stopped on rope when the air started to seem thin, if I held my bic
lighter over my head, it functioned normally. When I drew it down to
my waist, the flame began to separate from the lighter, & by the time
I lowered it to near my feet, the flame was over an inch above the
lighter & barely burning. This was probably 30-40 feet below the
entrance.
On Jun 13, 2010, at 8:20 AM, Philip L Moss wrote:
I can think of a few trips personally where the carbide lamps were
the only indication of high CO2/low O2. More than once I have
rappelled into bad air and knew almost immediately by the response
of my carbide lamp. The most recent time was less than a year ago.
No LED light will tell you that. For those of you who don't have
much experience with low O2 in caves, it can be highly stratified in
caves. I have had my head in 15% 02 while at my feet it was 9% (I
had a meter that day). OSHA forbids working in atmospheres below
18% O2, if memory serves. At 9%, one passes out very quickly.
--- End Message ---
--- Begin Message ---
Very similar experience in Midnight cave about 12 years ago on an aborted
trip.
I was first down. It seemed awful dank from the beginning but near
touchdown on the garbage pile, it got so bad I was having trouble breathing
- I could "feel" hyperventilation coming on . (No CO2 monitor, no lighter
even - but that might have been a good idea)..
Quickly changed over and ascended the hell outta there. It was one of those
cases where you consider that if you hadn't acted fast, you might just not
have had a happy ending! (And of course, fresh air on the surface was like
a big cold glass of water after hiking out of the dessert - SWEET!)
-WaV
--- End Message ---
--- Begin Message ---
Someone ought to post more on this subject because of the potential for
Hazardous levels of Carbon Dioxide in many areas of Texas.
We seem to have been blessed with a lot of karst (Ellenberger primarily)
prone to generating high levels of CO2 in the warmer months. I can tell you
that it can certainly present a life threatening scenario where vertical
caving is concerned.
I have been in very low air while crawling around and it can be very
disconcerting but one can generally evacuate to better air or be assisted.
On rope in still air it can most certainly become life threatening very
quickly when rappelling into a pool of Carbon Dioxide. I became severely
disoriented and made an emergency egress after fast rappelling 75 feet into
a cave in Cedar Park and hitting the bottom in what was probably life
threatening levels of CO2. Had I not made it out it would probably have
been a body recovery and could have involved more than one person if another
caver had descended to aid me not knowing the nature of the emergency.
You should be aware that CO2 is a common occurrence in many caves and if you
are on rope descend with caution should you notice bad air. It doesn't mean
it will be life threatening but the change can occur very quickly and one
needs to be prepared, should the air suddenly become extremely bad, to
change over and get the hell out post haste.
I know decomposition of organic debris is the primary cause in most caves.
Not sure what research has been done on this phenomena or why it seems to
occur mainly in many Ellenberger caves. Want to say this is an oil bearing
rock and CO2 may be the result of microbial activity? Any comments on this
from someone in the know.
Scott
_____
From: Don Cooper [mailto:[email protected]]
Sent: Sunday, June 13, 2010 4:36 PM
To: Chris Vreeland
Cc: Cavers, Texas
Subject: Re: [Texascavers] carbide vs LED (attempt 2)
Very similar experience in Midnight cave about 12 years ago on an aborted
trip.
I was first down. It seemed awful dank from the beginning but near
touchdown on the garbage pile, it got so bad I was having trouble breathing
- I could "feel" hyperventilation coming on . (No CO2 monitor, no lighter
even - but that might have been a good idea)..
Quickly changed over and ascended the hell outta there. It was one of those
cases where you consider that if you hadn't acted fast, you might just not
have had a happy ending! (And of course, fresh air on the surface was like
a big cold glass of water after hiking out of the dessert - SWEET!)
-WaV
--- End Message ---
--- Begin Message ---
Elevated CO2 is a common occurrence in Texas caves with the highest levels
typically being found in caves developed in the Ellenburger or Austin
Chalk formations. Both of these formations have low permeabilities, and it is
conjectured that this impedes the ability of CO2, once it accumulates, to
absorb back into the rock/water portion of the formation. That said, even
caves developed in formations with higher permeability and/or restricted air
flow may have elevated levels of CO2; usually not in amounts that cause
physical distress.
As to the cause of high CO2 levels, there are several possibilities:
1.) microbial decomposition of organic matter
2.) excessive degassing of CO2 from formation water at the water/air
interface
3.) degassing and/or breakdown of carbonates due to hypogene fluids moving
up from depth (these fluids may be related to hydrocarbons or igneous
activity)
4.) Excessive human respiration in restricted passages
Bill Elliott and Butch Fralia conducted oxygen (O2) and carbon dioxide
(CO2) studies in several Texas caves and found that the amount O2 and CO2 in
the cave air usually added up to approximately 21% of the total composition
of the air no matter what the relative proportions of the two gases were.
Normal air contains 20.9% O2 and 0.04% CO2 by volume. In caves with bad
air, the CO2 typically displaces the O2 proportionately so that if CO2 levels
approach 4%, then O2 levels are usually 17%. It should be noted that this
relationship does not always apply !
To test for CO2, use the BIC lighter test that Butch Fralia published some
years ago:
"I've followed the air quality measurement comments of the last few Digests
with great interest. Over the last nine years I've participated in a
volunteer cave research project at a Texas State Park. Of the 150+ caves on
the
park, the majority have some level of measurable CO2 accumulation ranging
from detectable to deadly. Over the course of this project, the state has
furnished air quality instruments for our use. One is an electronic oxygen
meter and a Draeger device. Using these instruments, we've taken literally
thousands of air quality measurements.
"The Draeger instrument was by far the most reliable. The problem with the
Draeger is the high cost of the tubes, of which one is expended with each
measurement and not reusable. The Oxygen meter has a probe that must cleaned
often and replaced about every three months. I don't know if later model
instruments have this same problem. The oxygen meters are calibrated on the
surface at 21% oxygen. It's easily knocked out of calibration while moving
through tight passage areas.
"Unless a caver is involved in a research project such as the one on the
state park, the cheapest and most reliable air quality instrument available
is a BIC lighter. It can be obtained for about $0.97 at any convenience
store and easily replaced when damaged or depleted. It's within the budgetary
range of anyone who can afford to go caving in the first place. This may
sound like a cop out to the folks who've offered all the fine advice on air
quality instruments but......read on gentle caver!
"When caving in the Arbuckle Mountains, the BIC was the air quality
instrument of choice though at the time, no one knew how reliable or accurate
it
was at the time.
"During the course of the state park project, we became curious at what
oxygen levels the lighter would start reacting. Using the instruments we set
up a number of controlled experiments and verified them with a number of
repetitions over several years with different brands.
"The lighter will start reacting at 19.5% oxygen. The flame changes color
and a small gap will begin to be noticeable between the flame and the jet.
At 18% oxygen, the flame will burn about 1 inch above the jet. At 17%
oxygen, the lighter goes out and can not be relit. As mentioned earlier, these
measurements were very repeatable and could be verified by anyone with the
instruments to do so.
"In our tests, 99% of the time the oxygen was displaced by an equal amount
of CO2, such that 17% oxygen = 4% CO2. This was not always the case! In
two caves, the measurements were typically out of balance where the CO2 was
2% higher than indicated by the oxygen level. This was repeated over years
of data! At the very least, when the lighter no longer burns, STOP!
"I should mention at this point that the physiological effects of bad air
result from the CO2 rather than oxygen deprivation! Most cavers, unless
they are asthmatic, can tolerate 17% [O2] without much difficulty; they will
breath heavier than normal for the amount of work being performed. At CO2
levels > 2%, the caver should cave slowly! Especially when climbing! High CO2
will result in a much higher rate of breathing, the skin will be flushed
to pink, and you feel hotter than you'd expect in a 68 degree cave.
Hallucination, panic and even passing out are typical reactions, especially
when
the CO2 level is greater than 4%. Coming back to the surface, headaches and
even severe nausea may be experienced. This can be prevented by stopping in
an area that has between 18% to 19% oxygen for at least 15 minutes before
moving on to normal air. Those of us who smoke seem to be able to handle
higher levels of CO2 than non-smokers since we're used to poor air quality
anyway.
"If you can afford it and want to play, buy the Draeger for a reliable and
accurate instrument, otherwise 'Flick you BIC!' (Fralia)"
_http://thelances.org/hr3/badair.html_
(http://thelances.org/hr3/badair.html)
Jerry.
In a message dated 6/13/2010 10:46:32 P.M. Central Standard Time,
[email protected] writes:
Someone ought to post more on this subject because of the potential for
Hazardous levels of Carbon Dioxide in many areas of Texas.
We seem to have been blessed with a lot of karst (Ellenburger primarily)
prone to generating high levels of CO2 in the warmer months. I can tell you
that it can certainly present a life threatening scenario where vertical
caving is concerned.
I have been in very low air while crawling around and it can be very
disconcerting but one can generally evacuate to better air or be assisted. On
rope in still air it can most certainly become life threatening very quickly
when rappelling into a pool of Carbon Dioxide. I became severely
disoriented and made an emergency egress after fast rappelling 75 feet into a
cave
in Cedar Park and hitting the bottom in what was probably life threatening
levels of CO2. Had I not made it out it would probably have been a body
recovery and could have involved more than one person if another caver had
descended to aid me not knowing the nature of the emergency.
You should be aware that CO2 is a common occurrence in many caves and if
you are on rope descend with caution should you notice bad air. It doesn’t
mean it will be life threatening but the change can occur very quickly and
one needs to be prepared, should the air suddenly become extremely bad, to
change over and get the hell out post haste.
I know decomposition of organic debris is the primary cause in most caves.
Not sure what research has been done on this phenomena or why it seems to
occur mainly in many Ellenberger caves. Want to say this is an oil
bearing rock and CO2 may be the result of microbial activity? Any comments on
this from someone in the know.
Scott
--- End Message ---
--- Begin Message ---
There are a bunch of new LED flashlights and headlamps to talk about,
but the only one really interesting to me is this one:
http://www.brightguy.com/products/Energizer_Night_Strike_Handheld_Light_3AA_ENSHH31L.php
I played with it at Gander Mountain today. I think they wanted $
77 for it, which is way too much,
but I did like the features it had.
Because of its flat shape, you could mount it on the side of your
helmet, but it may be too
big and heavy for that.
--- End Message ---
--- Begin Message ---
I have a question, or questions.
Do cavers still place numerical metal tags at caves?
Do any caves still have the old metal tags around them ?
My memory seems to recall seeing a round tag a little
bigger than a quarter with a number on it at a cave I
once went to.
I can't remember if I saw that at CBSP or somewhere
else where cavers were marking caves. Maybe out
at Bandera ?
If my memory is correct, was this a grotto thing, or a
TSS thing, or some other group?
--- End Message ---
--- Begin Message ---
Using metal strips or tags was once a popular method of marking stations in
Texas caves. You can still find them in some of the caves that were
surveyed back around the 1960s. I still use colored aluminum tags for
permanent
stations that I want to easily relocate.
Jerry.
In a message dated 6/13/2010 11:08:19 P.M. Central Standard Time,
[email protected] writes:
I have a question, or questions.
Do cavers still place numerical metal tags at caves?
Do any caves still have the old metal tags around them ?
My memory seems to recall seeing a round tag a little
bigger than a quarter with a number on it at a cave I
once went to.
I can't remember if I saw that at CBSP or somewhere
else where cavers were marking caves. Maybe out
at Bandera ?
If my memory is correct, was this a grotto thing, or a
TSS thing, or some other group?
--- End Message ---
--- Begin Message ---
Is this a French version of the Terminal Siphons ?
http://musikplease.com/theant-sporto-kantes-speleology-11470
Whatever, it is they stole the idea from the old
Buck Rogers movie ( 1979 )
http://www.youtube.com/watch?v=RHG29QjqYZ8&feature=related
--- End Message ---
