As a career NASA Space Life Sciences Engineer, I realized that there are many potential lessons to be learned directly and personally about human physiology when immersed in an alien environment. Sure, we can call it an “off-nominal” environment or an “other-than-one-Earth-normal” environment. But let’s just call it what it is – an environment where humans cannot survive unless they bring their own life support system. Like I said, an alien environment. And it was in one of these alien environments that I discovered that I was a nitrogen canary.
Long before the days when there were such things as life support systems with integrated instrumentation, miners brought canaries in cages down into the mines with them. If the canary stopped its typical incessant chirping and was found lying on the bottom of its cage feet up, it was the signal to drop their picks and hurry to the surface. Why? Because canaries have a significantly more sensitive physiology to many invisible, odorless gasses that kill humans – so it would kill the bird first, leaving the miners time to escape.
Even with today’s highly instrumented advanced life support systems, there are canaries among us as extra-sensitive human crew members… and I am one of them. I have discovered empirically, in vitro, that I have a double sensitivity to carbon dioxide and nitrogen.
Nitrogen is an inert gas which makes up nearly 80% of the air we breathe. It is also the prime gas responsible for giving SCUBA divers the bends. Here is the story of how I discovered the effects of nitrogen on my canary physiology.
Claudia and I were on a NASA undersea mission in 1995 prepping for an upcoming mission to test Advanced Life Support concepts and equipment in a remote and extreme environment. We were preparing for what was planned to be the longest aquanaut mission on record – 90 days of continuous submersion. Unfortunately, the actual mission was cancelled in 1996 due to budget constraints. But on this 1995 undersea run, we were submerged underwater for two continuous days installing equipment that would calibrate and log our heat exchange equipment since our gear would generate considerable waste heat during the 90-day non-stop run.
We submerged mid-morning and headed down to the MarineLab habitat where we would be testing our gear. Later, we swam over underwater to the Jules Undersea Lodge where we would be sleeping, dining, and observing our portable instrument cluster that monitored the experiment in the adjacent undersea lab. The experiment was designed to run continuously for 36 hours.
Our depth in both habitats was 30 feet, but the habitat’s moonpools (opening to the sea) were engineered to be at a depth of exactly 21 feet of salt water (fsw) – the limit for non-decompression saturation diving. Thus, we were living at a pressure of 21 feet fsw. In just 9 hours, our blood became totally saturated with oxygen and nitrogen – the basis for the label of “saturation divers.” After 9 hours, the saturation was complete, and no more gases could be dissolved in our blood.
However, as all divers know, returning to the surface after saturation will cause the excess gas in the blood to come out one way or another. In our case, right at the very limit of no-decompression diving, the gases would evolve more slowly as microscopic bubbles that could be safely eliminated without a decompression schedule when returning to the surface. After testing hundreds of divers, 99.9% did not get the bends on this schedule at this depth. But every diver would, nonetheless, “naturally” decompress upon arriving at the surface, evolving microscopic bubbles of nitrogen through their lungs. After our 48-hour run, I discovered the hard way that I was not one of the 99.9%.
At the end of our dive mission, we hauled a lot of heavy equipment to the surface. And, as soon as it was all on the pier, we immediately began to carry it to the van for transport back to the Kennedy Space Center. At the end of that cycle, I suddenly discovered that I did not have the energy to walk more than 15 feet without stopping to catch my breath, as though I was working at a high altitude. I also developed a terrific headache, and a bright red rash began to appear on my abdomen.
Claudia saw my flushed face and asked what was wrong. I replied, “I think I just got bent” – diver’s slang for getting the bends. She responded with what I was also thinking, “But the Chief Aquanaut said you can’t get the bends at 21 feet saturation!”
I nodded and very much wanted to believe that was true. Ultimately, I made up my mind and settled on a final self-diagnosis – it was stress and fatigue, not the bends, which apparently was not a possible affliction for me. While there was an emergency decompression facility just a few blocks away, and while I had diver’s insurance that would pay for its use, being treated for the bends would most certainly end my NASA Aquanaut career for good.
I had been with the Agency long enough to know how that would be received back at the Space Center, so, no, I did not have and could not have the bends. Period. But I also knew that, if it was a nitrogen incident, not treating decompression sickness as an emergency could result in paralysis or even brain damage.
At Claudia’s urging, I sat down under the covering of a nearby veranda, drank a bottle of water, and put my feet up. After about half an hour I felt much better. The headache was going away, the rash was fading, and my energy was returning. She insisted I stay out for another half hour before moving, ready to call 911. By the end of that hour, I was nearly back to normal, and I walked to the showers to get out of my dive skins and change for the ride home. All was well; the event was over. Well, almost….
On returning to the Space Center, I sought out a friend of mine who was a NASA Astronaut Flight Surgeon as well as a Hyperbaric Physician qualified to treat divers with the bends. Under patient-doctor confidentiality, I let him know what happened. His reply was simple: “You had a mild case of the bends. You were very lucky.”
Then he told me something I did not know. Every astronaut who engages in space walks, or Extra Vehicular Activities (EVAs), goes through an almost identical physiological scenario as a saturated aquanaut at 21’ fsw. While preparing for an EVA, pressure in the spacesuit is reduced to 4.3 psi (pounds per square inch) from the Space Station’s 14.7 psi. This allows the astronaut to move about and use their gloves more effectively while working outside the space station in the vacuum of space.
However, the reduction from the station’s to the suit’s pressure results in nitrogen saturation micro-bubbling in their bloodstreams right at the limit, exactly as in our underwater expeditions. Therefore, astronauts pre-breathe oxygen to flush the nitrogen out of their system before reducing their suit pressure, and they must sit with their feet elevated in a relaxed position for about an hour to prevent micro bubbles from being converted into larger bubbles caused by the cavitation of the large hip, knee, and arm joints.
I immediately adopted the astronauts’ “decompression protocol” from the space station for all our future NASA undersea operations.
But ultimately, you see, I was truly a one-in-a-thousand aquanaut ever documented with this condition after saturation at 21’ fsw – a true nitrogen canary.
On our next undersea mission, I pre-breathed oxygen before surfacing, later replacing that pre-breathe with a 15-minute decompression stop at 12 feet. We also required every diver, upon surfacing, to immediately sit in a lounge chair at the end of the pier, feet up, for a half hour. I never had another incident, nor did any of our many other aquanauts during the next three years of undersea operations.
(Shown here is me and Rod Roddenberry – son of Star Trek’s Gene Roddenberry (left) – in his surface decompression mode after his 24-hour mission where he was certified as an Aquanaut.)
What did this experience teach me for later life? A lot, actually. The first lesson is that everyone gets totally saturated with what they completely immerse themselves in. If it is destructive anxiousness or fear or rage learned from an immersion in temporal-focused media, then all that negativism will come out in other parts of our lives. If we absorb it – then it must come out. Nature will not allow otherwise. And exactly like the bends, you never notice it until it is too late.
The other thing I learned is that even a nitrogen canary can bypass the bad effects – but only if they understand things clearly at the physiological level, and then very carefully comply with the instructions to keep the consequences from happening.
Life is like that as well. Immersion in positive, good things – like the Word of God or even the Templars – will result in those character aspects seeping out from our lives every day. From saturation with the Word of Life will emerge an extraordinary life of joy and freedom. And from saturation with the Templars will emerge an individual of integrity, chivalry, sacrifice, and service.
We live in an age of information overload, and all of that data is trying to get inside and saturate our being. But as Christ Followers, we are likewise living in an age of the extraordinary power of supernatural discernment, blessed by the indwelling Holy Spirit of Grace Who will teach us the real, unmolested truth. As Jesus said, “But when He, the Spirit of truth, comes, He will guide you into all the truth….” (John 16:13)
Being a nitrogen canary taught me a lesson for a lifetime: Whatever I immerse myself in totally, those things become who I am and define what comes out of me to those I love, and ultimately to the world.
We are beings of choice. We get to decide. Personally, I decide to be filled with the peace and love of God. All the rest is just too much nitrogen. So, relax, immerse your life in the goodness of Christ, put your feet up, and enjoy the peace of the Kingdom and not all of the runaway inert gas narcosis of the world.