What happens with the volume of oxygen within the cylinder as the temperature decreases?
I am a Civil Engineer, so forgive me if I get a little technical here, but I think it’s important to understand how gases behave inside cylinders when you vary the temperature. This behavior is roughly governed by the Ideal Gas Law. Without going into all the technical details, although I am happy to supply them on request, the volume of oxygen inside the cylinder will change in proportion to the changes in temperature as measured in degrees Kelvin. To convert from degrees C to degrees Kelvin, just add 273 to degrees C. So a bottle at -25C will have about 23% less liters of oxygen in it than the same bottle at +50C (1-323/248). This means that a Poisk bottle that starts out with 1280 liters at +50C, will have 982 liters of oxygen in it at -25C. An IMG bottle with 1800 liters at +50C will have 1366 liters at -25C. You can see this in action on the mountain – you’ll notice a reasonably rapid drop in your pressure gauge as the temperature cools when the sun goes down. This is because ther
