Air, Water and Food (Part 3)

Of all the essentials of life air is one that no-one can do without. It is life’s medium. We breathe it constantly and without it we are dead in minutes.

Our atmosphere is 21% Oxygen and 78% nitrogen the other gases are les the 1%. When we breathe we exhale 16-17 % oxygen. Which means that we only really use 4-5 % of the oxygen mixture. Yet, if the air quality were reduced significantly there would be a tremendous increase in respiratory illness and many fatalities due to only a minor change in the percentage of the air mixture.

For many of us air is free, at least for all the healthy land dwellers. Even whales don’t pay for air. Fish extract the air they need from water, a technique that is being developed for human underwater use also. Generally we have not monetized air. Yet for me I know generally what air costs.

As a scuba diver my 80 or 100 cu.ft. tanks of compressed air cost about $5 to $10 per to refill. This amount of air would last approximately 45 minutes to an hour, as long the diver didn’t go too deep or do much strenuous work. So if you are to breathe “store bought” air for 24 hours, 7 days a week, 365 days a year it would cost approximately $61,320 for one year. Lucky for us we don’t need to buy air for everyday use, at least not yet.

Scuba divers have also developed and used different air mixtures. Nitrox also known as enriched air; it contains a greater percentage of oxygen than normal air. By adding oxygen and removing nitrogen the diver reduce fatigue and also lowers the chance of nitrogen narcosis, which is a build up of nitrogen in the body; commonly called the “bends” because it can lead to sever pain in the joints of the body. Nitrox can range from 22% up to 40% oxygen. But because oxygen is toxic and can lead to blackouts at high levels in your body, it is not used deep dives (general 110 ft max). This is all due to physical properties of dissolved gases in our blood steam, size of air bubbles and partial pressures. If you are interested in this see this posting regarding dive tables and decompression needs for divers. http://www.sdm.scot.nhs.uk/dive_tables/

So increased oxygen helps with respiratory issues and overcome fatigue. There are patients with respiratory conditions that are prescribed medical grade gases such as nitrox for home use to keep them alive. This air costs a bit more then what I factored before.

Back to my scuba example, when divers want to do deep exploration even the 21% oxygen found in normal air can be dangerous. tanksMore importantly the high nitrogen creates a euphoric experience that has been compared to being intoxicated. Scuba divers refer to this as “martini’s law” each atmosphere below 90 ft can be equal to having one martini, straight up, no rocks, no olive. You really don’t want to be drunk down at 180 or 200 ft.. It could very well kill you. To offset this effect deep underwater divers have experimented with different mixtures. Trimix or heliox are commonly used. What these gas mixures do is reduce the Oxygen levels down to 15-17 % lowering the amount of oxygen, thus reducing the oxygen toxicity to prevent deep water blackouts, which are fatal. Then they replace 40-50% of the nitrogen with helium or another inert gas that we don’t process or retain in our system. By lowering the nitrogen the effect of narcosis is reduced. Of course your voice has a distinct Donald Duck sound, if you are using two-way radios to communicate. The cost of such mixtures can be very high at least compared to “free air”.

Without air we die, so if a comet were to brush by earth and strip away our atmosphere there is little we as humans could do. While this is unlikely, we are now altering our atmosphere gradually and eventually changing the air mixture.

Many of us could survive with 16 – 17% oxygen mixture, with higher CO2 in our air we would see a increase in respiratory issues and heart attacks; I know I hadn’t mentioned this before as we exert ourselves there is increased heart problems due to lack of oxygen in our blood. These individuals would likely then need to buy enriched air just to survive. Still many will die sooner then they normally would have. The rest of us would adjust, until the next decline in oxygen, then we would all would be supplementing our free air with canisters of enriched air the same way we use bottled water instead of free rainwater or tap water (yes, I know we pay for tap water too).

The environment is seen by some people as being “out there”; somehow disconnected or disjointed from ourselves. This is not the case, the environment is the air we breathe, the water we drink and the food we eat. It is all connected. When we look to save the environment we aren’t saving the planet we are attempting to save ourselves.

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