Around the World Submerged: The Voyage of the Triton

We discovered other phenomena, too. For example, increasing the pressure of the ship’s internal atmosphere had no effect upon the percentage of oxygen it contained, but it did have an effect upon the total amount of oxygen in each cubic foot of atmosphere. Thus, deliberately increasing the air pressure in the ship by a pound or so per square inch greatly improved the ability of our laboring lungs to draw in oxygen, and consequently everyone felt better. The difficulty with this scheme was that as soon as we began ventilating to the atmosphere, the pressure would reduce to normal. If we luxuriated in hyper-pressure atmosphere for too long a period, some of us might temporarily be exposed to an atmosphere below the minimum allowed oxygen content before our ventilation blowers had managed to sweep out the bad air.

It is remarkable how much stability the human body requires within the wide range of the possible conditions of nature. Ideally, man should be in a temperature of around 70°; by various stratagems, he is able to exist over a temperature range of perhaps 120°, centered on the 70° midpoint. But temperatures in nature can go down to a minus 459° F—which it does in outer space—or up into the thousands of degrees.

Man is acclimated to twenty-one percent of oxygen in the air at normal pressure. He suffers acutely if the oxygen percentage drops only a few points, to seventeen percent, for example, or rises much above twenty-one percent. At the time that we in Triton began to feel distressed, we would have consumed only one-sixth of the available oxygen in the atmosphere of the ship. Were the oxygen percentage to rise above the norm of twenty-one, we should probably experience most of the effects of ordinary intoxication.

There was really nothing unusual in these “discoveries” which we were making; submariners have known and applied the principles for years. But there is no substitute for experience, which opens many new avenues of inquiry.

For example, there was the question whether gradual oxygen reduction each day for a prolonged period would have any damaging consequences on us. The effects of depriving the human body of oxygen all at once to an excessive degree are well known. But what about minor deprivation for many days? No observable deleterious effects have been noted, but many highly qualified medical people have recently been devoting considerable research to this question. The problem ranges from the physical to the psychological, from an environment of oxygen deficiency to one in which the entire atmosphere is mechanically controlled and stabilized at some optimum point.

From the Log:

The Medical Research Laboratory in New London has been pursuing this particular project for a long time, the first announced test being Operation Hideout in the mothballed submarine Haddock in 1953. Doctors Ben Weybrew and Jim Stark have been discussing the sealed-atmosphere test for several days, and finally have proposed a procedure. We will remain sealed for approximately 2 weeks, running various physical and psychological tests among selected volunteers from the crew. Somewhere during the mid-point of this period we will put out the smoking lamp for an extended time. Careful checking of all factors will continue for several more days before terminating the study.

The purpose of the no-smoking test was partly psychological, but there was a question of atmospheric research, too. Smoking, nuclear submariners had discovered, was their only source of carbon monoxide. In a completely sealed atmosphere, accumulation of carbon monoxide could not be permitted because of its deadly brain-damaging tendency. Expensive equipment had been devised and installed to convert it into carbon dioxide, so that it might be “scrubbed” from our atmosphere along with the carbon dioxide exhaled from our lungs.

One of the questions raised was whether or not this equipment was worth the cost; or whether it would be better to prohibit smoking in a completely sealed atmosphere, instead of going to the added expense and trouble of installing the carbon-monoxide removal apparatus purely because of the psychological satisfaction that some men got out of smoking. All this, of course, has a direct bearing on the endurance of submarines at sea—their ability to cope with the various problems they would undoubtedly encounter, and the efficiency with which they might be expected to operate under various severe conditions. The data that we were helping to gather would become available to our first space pioneers also.