This report was copied/pasted from the Main Forum, July 11, 2004 The following is my attempt to relate a bizarre episode I experienced during a recent dive at Ginnie Springs. Included is as much applicable information as possible, which myself and numerous others have already evaluated in an attempt to determine the cause of the incident.


Saturday, June 26, 2004 POTENTIAL PREDISPOSITIONS:

Earlier in the day, I conducted a dive at Diepolder III at ~11:00 a.m. It was a nice, laid-back swimming dive, with a maximum depth of 268ffw (brief exposure). Most of the dive was at a shallower depth, perhaps 210ffw. Backgas: 12/60/28; deco gas: 50/30/20 and 100% O2. After doing a lap, we were back at the chimney at 30 minutes. Very conservative deco schedule, as the depth and time was less than anticipated. Dinner at Floyd’s around 7:00 p.m. Mike’s Salad topped with a blackened chicken breast. I was well hydrated, having been drinking water extensively throughout the day. Bottom line was I felt 100% A-OK.


THE GEAR: Breathing gas was 32.1%, as analyzed before the dive, in a set of 121s (all my sets had high helium mixes, so I borrowed a friend’s set), and 100% O2 in an AL40. The 121s were broken down just over a month prior to this event and VIPed; manifold was ultrasonic cleaned, rinsed, and re-assembled; just over 500psi of aviator-grade oxygen filled in the tanks to allow for an air top to yield EANx 32; the air top-off was completed at the end of a caving trip the following week, and the tanks sat in the garage until this trip, approximately a month later. All regulators were working fine. I was diving dry with 400g undergarment; no hood.


BUDDIES: Joe Citelli and Heather Choat.


THE DIVE: We had planned to do a scooter dive in Ginnie, but one of the three-person team had issues with their scooter so we switched to a swim dive. Planned route was to take the Hill 400 Line to the Double-Lines. I am fairly familiar with Ginnie, and have been up and down the Hill 400 Line many times, both swimming and scootering. I was leading, and headed into the Ear. We dropped our O2 bottles off at the rock next to the tunnel to the Eye. I swam at a moderate pace down the Gallery to the Lips, shot thru, and waited off to the left very briefly for the rest of the team. (NOTE: one of the other team members thought I blitzed through the Gallery at a rapid pace, while myself and the third team member thought it was only a moderate pace. While I swam at a good clip – to get out of the flow ASAP – I did not feel like it was excessive or caused any dramatic increase in consumption, fatigue, etc.) Popped thru the Keyhole, and got out into the main tunnel. Proceeded to the jump off to the left to the Hill 400 Line. I slowed down to a normal cave swimming pace, and allowed Joe and Heather to pass in front of me, as Joe was going to run the jump to the Double Lines. Somewhere at this point, I noticed a very odd taste in my mouth; to be more precise (or maybe not), my tongue felt very, very odd. It was like a rubbery taste – very distinct. I apparently slowed down even more, as the separation distance between myself and the other two divers increased slightly. I started feeling increasingly “odd.” I noted Joe preparing to run the jump to the Double Lines (~1000'), and I approached Heather and signaled to turn the dive. I did not thumb it, but simply signaled to turn. I remember taking my regulator out and sticking my tongue out while making a contorted face, trying to communicate that something was bizarre with my tongue. It was hardly a definitive signal. Heather gave an inquisitive look and promptly made a motion to offer the long hose, but I shrugged it off. This is pretty much the last thing I distinctly remember until getting up through the Keyhole again. (The following will seem very bizarre – I will try to do my best to convey what I was thinking and what I was doing. It may not help much. There are distinct gaps in my memory, but I oddly remember other portions, though they appeared “dreamlike.” I encourage Heather and Joe to add their observations.) Upon turning, whatever was going on intensified. My peripheral vision and depth perception seemed impaired. I recall at points having my hands out and not being able to judge exactly where the rock was. At the same time, my mental capabilities were severely impacted. I recall evaluating whether I should bailout to my buddy’s long hose, as it seemed apparent that I was experiencing a gas problem. However, I could not come to any resolution and it seemed like my thought process was in a non-stop loop, continually asking myself “maybe I should bailout to their gas” over and over again. Also at this point (keep in mind, while these descriptions seem sequential, they were more or less occurring simultaneously), I became totally confused to where I was. Not merely to the point of “where in Ginnie am I?” even though I knew this section of cave well, but to the point of “I appear to be in a cave – I wonder what I am doing here?” The harbinger of the whole episode – the odd taste and feeling on my tongue – had intensified to the point where my tongue was basically numb. I was swimming next to the line, and (I believe) OKing it most of the way out, even though the tunnel was crystal clear. I did not feel any anxiety or panic, as for some reason this seemed familiar to me. I was almost intrigued with my surroundings, though definitely perplexed at the same time. Next thing I remember was getting back to the main line. I distinctly remember asking myself “that line is yellow and this one is white, I wonder what that means.” Also, “all those arrows must mean something.” Heather, who was pretty much on top of me for the swim out, I believe realized something was really not right at this point as I paused and kept moving my light up and down the main line. At this time, I was trying to figure out where to go – I was that impaired that although I saw these little arrows pointing in one direction (should be pretty intuitive, right?), I could not make the mental connection. Fortunately, Heather edged up on my left shoulder, basically blocking me from going farther into the cave. “Hmmm, she doesn’t seem to want me to go this way” I was thinking. To better describe my mental condition at this point – upon seeing Heather I recognized that she was very familiar to me, but if you were to ask me her name at that point I would have been hard pressed to provide it in a timely fashion. In short order, we were at the Junction Room and I vaguely recall looking around thinking this area looked cool, but definitely still not sure of my surroundings. I traced and retraced the route of the line with my light trying to follow where it went. I slowly meandered along the line with Heather right on me, and eventually popped up through the Keyhole. As the current pushed me over the rock towards the Lips, it was almost as if I was coming out of a mental fog. Things started making sense again, and I knew where I was. At this time I was aware of a mild headache, and very mild nausea. We made our way to our deco gas, and I remember looking up at both my buddies as I fumbled with my bottle a little bit, and could see the concern in their eyes. I signaled “OK.” At this point I had my mental faculties back, realized it was bad gas, but also realized that the effects were greatly diminished. I simply wanted to get to O2 as soon as I could, so opted not to go on a long hose for the short hop thru the tunnel to the eye. I got on O2 at about 30 minutes (I think) run time, and breathed it for ~5 minutes as a precautionary measure. I could feel myself returning to normal, and just relaxed as the majority of symptoms and signs passed.


On the surface, we drifted down the run and chatted. One of the first things I said was something along the lines of, “That was not cool.” I explained what happened and how I felt “fucked in the head” to put it bluntly. I was having a hard time describing anything that made sense. Even though I thought it was gas-related, a part of me was worried that it could have been physiological. The first theory was hypercapnia. However, I felt that the swim into the cave was not sufficient to induce it. Having experienced the distinct effects of hypercapnia before, this was not the same. Further, since I was not expending hardly any energy for the majority of the way out and the condition did not resolve itself, the possibility of hypercapnia was discarded.


I remembered the taste on my tongue and felt that it was an indicator of something. Heather tried my gas and confirmed my suspicion that the gas was tainted, and had a distinct flavor to it. Within an hour or so, I felt pretty much completely normal, though I did have a nice series of unpleasant vurps (i.e., vomit burps). The next day we were getting fills at the same place we suspected the original air top-off came from. Since it was late when we finally got out of the water the night before, I had not broken down the gear yet. At this time, Joe got a good taste of the funky flavor. Trying to eliminate possibilities, in this case mold or any other contaminant in the first or second stage, we tried another regulator. Same result. We tried the gas directly from the manifold, and the odor was very strong. Recognizing that the sense of smell can be subjective, we asked the individual working at the shop to check it out, to make sure we weren’t crazy. He also smelled the strong odor. We all tried to figure out what this odor was. The shop had a CO meter, which we tried to test the tanks, and it appeared there was no indication of CO. The individual at the shop thought about the possibility of oil contaminant, so we checked out their synthetic oil to see if the smell was familiar. BINGO! SUMMIT DSL-125 synthetic oil lubricant. The smell was so distinct, we all felt confident this was the same odor as that of the tainted gas. We checked their air fill whip, and it too seemed to have the same odor, but definitely not as strong as the tainted gas in the tanks (though they were filled about a month earlier). We also checked a set of Joe’s tanks that were just topped off with air. However, these did not seem to have an odor at all. Bizarre. It should be stated that the individual working at the shop, while mentioning he was not aware of any other incidents such as this or any complaints of bad gas, was genuinely concerned about the safety of the gas; he was nothing but completely professional. Regardless, with the odor potentially identified I felt comfortable we had an explanation for what happened, even though we didn’t understand the exact mechanics behind it. (Everyone that we asked to smell the tanks while in cave country identified the strong, distinct odor within seconds of cracking the valve.) We figured a subsequent gas analysis would reveal what contaminants, and their respective concentrations, were in the tank. In the meantime, I obtained the material safety data sheet (MSDS) for the synthetic oil. It was of little value, but I have included portions of it herein for informational purposes: REACTIVITY DATA Hazardous Decomposition Products: Burning will produce toxic fumes HEALTH HAZARD DATA Effects of Overexposure: Low oral and dermal toxicity. Prolonged or repeated exposure may cause irritation, nausea, and vomiting. PHYSIOLOGICAL EFFECTS SUMMARY Respiratory System: Believed to be minimally irritating. I also contacted a friend of mine, Dr. Michael Ott, who is an undersea and hyperbaric medical physician, and the Diving Medical Officer for NOAA. He was very interested in the case, and was kind enough to try to track down some information for us. Dr. Ott contacted the actual manufacturer of the oil and talked to the lead science officer for the company, as well as the original PI who completed the MSDS. They were intrigued with the case, but also were unable to produce any data on the effects of inhalation of oil vapor at high partial pressures. More interestingly, Dr. Ott talked to Dr. Gordon Daugherty, who was one of a handful of diving physicians for the oil companies in the Gulf of Mexico several decades ago. He relayed anecdotal information on several similar incidents that were believed to have been caused by inhalation of oil vapors in the breathing media. Based on his communications with his colleagues and other information – keeping in mind it is hardly conclusive or definitive due to the lack of research on this potential interaction, and the absence of any allied neurological information – the consensus was that inhalation of oil vapor, an organic solvent, at significant partial pressures, could induce a transient neurological disorder; how one would determine the actual threshold for oil vapor partial pressure in this scenario is not known. Regardless, the effect of such an exposure was suggested to be similar to sniffing glue. The clinical description of this narcotic influence would seem to corroborate the signs and symptoms I experienced on this particular dive. Other descriptions to some of what I experienced would be similar to those of a stroke victim or someone suffering from Alzheimer’s. It was definitely a weird episode, and in retrospect it is uncomfortable to realize how diminished my mental faculties were on the dive, but thankfully nothing too severe in this case. Yet, after some discussion, the potential repercussions of such an exposure were sobering. A typical dive we conduct would have us breathing a stage and scootering to the Henkle, whereupon we would switch to backgas for a swimming dive back in the cave. In fact, we were planning just such a dive for that weekend. As many of you know, the cave past this restriction is exposed to very high flow, and portions of the tunnel require a significant amount of work. Had I not breathed my backgas until this point, and under heavy exertion, the consequences could have been catastrophic. EPILOGUE I had not posted this before due to our desire to obtain a valid gas analysis in order to reduce speculation. Unfortunately, this was hindered by the holiday weekend. I received the analysis yesterday, but quickly realized it was highly suspect. The analysis stated that the sample was within specs, and did not have any variable outside of acceptable thresholds. In particular, it stated that oil vapor was <1mg/m3. Further, their O2 analysis stated that the gas sampled out at 20.89%. HOWEVER, the gas in the tanks was analyzed by several individuals using at least two analyzers as 31.8-32.1% (it still analyzes out as that, as we are retaining the gas in the tanks until this is resolved). Therefore, it is questionable that the rest of the analysis is valid. There is no doubt in our minds that there is oil present in the tanks. Perhaps the sample kits were mixed up at the lab, the sample was compromised, the analysis was screwed up, or some other potential scenario occurred. The lab is interested in resolving this glaring discrepancy, and we will be delivering the tanks to their facility for a follow-up analysis early next week and I will post the results once we have them. The facility where we believed the tainted gas originated also had their gas analyzed, and it proved to be contaminant free.


The reason for posting this is simply to share information on an apparently very rare, potentially random, and relatively undocumented interaction. With recent fatalities attributed to bad gas focusing attention on carbon monoxide in compressed air, the potential introduction of oil vapor would appear to be another threat to diver safety. I will defer to others that have more experience and knowledge with compressor operations to chime in, but from what I have learned from some subsequent research, is that there is a very real potential for the introduction of oil vapor or oil aerosol from compressors operating at high psi and at high temperatures. When in vapor or aerosol form, it is difficult for filters to pick these contaminants up, and prevent them from migrating thru the system to wind up coalescing in a diver’s tank. If your breathing gas has ANY odor or taste, do not breath it. There is no such thing as air “smelling like compressed air.” There should be NO odor associated with safe breathing gas. This is something many of us overlook, as I have not made a conscious effort in the past to smell my gas before using. As silly as it sounds, I will be doing this in the future.