Everest oxygen week, Part II of III
12:26 p.m. EST Jan 28, 2004
For this week and next, ExplorersWeb is looking into a new ‘demand-based’ oxygen setup created for Everest. This week we’re publishing an interview with the system’s creator and next week will be an interview with a climber who used the system on Everest last spring.
Yesterday in ExplorersWeb’s interview with Neil Greenwood, the creator of the new system for Everest, we discussed the development, subsequent success, and the different way in which oxygen is delivered – through the nose. In today’s excerpt of the interview, Neil talks more about the development, his testing of Poisk’s setup, and different valve configurations.
ExWeb: Poisk has been the traditional setup; did you guys research into their system while developing your own?
Neil: We researched their product in depth. The Poisk system is very lightweight, simple to use and operates reliably, considering the environment. There are, however, certain areas that require improvement: efficiency, reliability, method of delivery and longevity. In addition to this there are many small but important details overlooked in their system.
We conducted some testing on the Poisk cylinders and found a large percentage of them to be micro-porous, or leaking. Poisk themselves only guarantee the cylinders for 2 years. The cylinders are not tested to destruction in the same way ours are. If one of our cylinders is damaged and punctured the oxygen will escape in a loud rush, however, the cylinder will not disintegrate, whereas, a Poisk cylinder may explode.
The Poisk cylinder valve is only designed to be opened once and doesn’t allow you to read the contents on a gauge without connecting the regulator, but due to the absence of an opening mechanism on the valve, connecting and disconnecting the regulator causes the escape of oxygen before you’ve even started climbing.
The facemask causes resistance whilst breathing and can give the feeling of claustrophobia. This restrictive breathing and claustrophobia is sometimes the cause of climbers not making it to the summit. Any increased resistance to breathing at that altitude places a huge demand on the respiratory system, requiring more energy. This additional energy draws on vital oxygen in the body for it to be produced.
ExWeb: In terms of leakage and lost air that you mentioned above, what did you implement in your system to overcome those issues?
Neil: Our cylinder valve has been specially designed. It has an ‘open’ and ‘closed’ position, which allows you to connect the regulator to the cylinder, open the valve to check the contents of the cylinder on the gauge on the regulator. You can then close the cylinder valve, release the pressure in the regulator and remove it. This results in a minimal waste of oxygen.
With the Poisk system you do not have this ability and the connecting and disconnecting the regulator results in the loss of a lot more oxygen. The only way to then gauge the contents of the Poisk cylinders is to weigh them with a set of scales. Our valve has another built in safety feature so that if the valve is accidentally opened with no regulator fitted, no oxygen will be lost, only when the regulator is fitted will oxygen be released.
In Part III of III tomorrow, Neil talks about longevity, weight, safety, and the type of oxygen used to fill the bottles.
Read Part III of III: here..
Poisk – Summit Oxygen quick comparison:
3L bottle – 615 USD, 3345g, 22.6 hrs of use on 2L of flow (20 breaths per minute)
Regulator & Dosage Regulator – 1680 USD (210g + 200g) = 410g
Total weight: 3755g
Total cost for 1 setup: 2295 USD
Refill from Summit 100 USD
3L bottle: 310 USD, 2600g, 6 hrs of use on 2L of flow
Regulator: 300 USD, 350g
Total weight: 2950g + mask
Total cost for 1 setup: 660 USD
Refill from Poisk: 120 USD
Summit: 22.6 hrs of O2 = cost of 2295 USD and weight of 3.8kg
Poisk: 24 hrs of O2 = 1540 USD and weight of 10.8kg (1 regulator and 4 bottles)
All information in comparison from respective company’s websites.
A member from last springs Royal Navy/Marines Everest expedition testing out Summit Oxygen’s rig in Base camp courtesy of RNEverestnorthridge2003.com