1. Oxygen Oxygen – the ‘Breath of Life’ “How high can I make it without extra O 2 ?” harry oxer

2. copyright Harry Oxer 5/2003 2 How much oxygen in air? At ground level: Nitrogen 78% OxygenOxygen21% Others 1% (mostly Argon)

3. copyright Harry Oxer 5/2003 3 How much oxygen in air? At 30,000’: Nitrogen 78% OxygenOxygen21% Others 1% (mostly Argon) Same percentages, BUT:

4. copyright Harry Oxer 5/2003 4 But…… Oxygen needs pressure to get into solution in the body And the pressure is MUCH lower as you get higher! Need a partial pressure of at least 60mmHg to force oxygen into solution in the body

5. copyright Harry Oxer 5/2003 5 Compare carbon dioxide 1000 L of CO 2 in an average room But all water doesn’t turn to soda water! CO 2 only dissolves if injected under PRESSURE If reduce the pressure enough – i.e. take the top off – all the CO 2 comes out of solution In space, even if lungs full of oxygen, you would suffocate, because all oxygen comes out of solution – no pressure to keep it dissolved!

6. copyright Harry Oxer 5/2003 6 Relevance of this? As you climb in sailplane, or any unpressurised a/c, the ambient pressure FALLS, and so does the partial pressure of oxygen Partial pressure – that % of the total pressure exerted by the oxygen, i.e. 21% CO 2 and water vapour further reduce the pressure available for oxygen

7. copyright Harry Oxer 5/2003 7 Pressure available to push oxygen into solution Pressure altitude – (ft) Atmospheric pressure mmHg Ambient O 2 pressure Alveolar(lung) O 2 pressure 0760159103 500063213381 10,00052311061 12,00048310154 13,0004659751 14,0004479448 15,0004299045 20,0003507334 25,0002825930

8. copyright Harry Oxer 5/2003 8 Oxygen pressure cascade Air 150 mmHg ▼ Alveolae of lungs 100 mmHg ▼ Tissues average 40mmHg If inspired pressure of O 2 less than 40mmHg, O 2 comes OUT of body!

9. copyright Harry Oxer 5/2003 9 flying Must maintain alveolar partial pressure of O 2 at least 60mmHg (more than 40 to push) How? Increase inspired partial pressure, by increasing %. e.g. 50% O 2 pressure 760/2 = 380 mmHg – 300mmHg in lungs! Plenty of pressure. Add oxygen to increase the driving pressure

10. copyright Harry Oxer 5/2003 10 10,000’ Lung O 2 pressure 61 mmHg – above the tissue 40mmHg OK if you are fit and healthy! 12,000 ’ Lung O 2 pressure 54 mmHg – just above the tissue 40mmHg – not much force to get O 2 in to solution! Above this level, RAPID decline!

11. copyright Harry Oxer 5/2003 11 Effects of hypoxia – low oxygen Insidious First to go is the ability to assess oneself Over-confidence and under-competence! Like alcohol CAN’T detect own symptoms! Use oxygen always, and early No room for under-performing pilots who don’t realise it - or dead heroes!

12. copyright Harry Oxer 5/2003 12 hypoxia Up to 10,000’ - normal individual: effects rarely significant 10,000-12,000’ – rapid decrease: –Complex eye-hand coordination decreases 10-12% @ 12,000’, 30% @ 15,000’. –Vision decreases from 8,000’ –Some > unconscious @ 16,000’! AND YOU DON”T KNOW!

13. copyright Harry Oxer 5/2003 13 hypoxia The most dangerous aspect of hypoxia is that the individual experiencing it does not and can not detect the decrement in function, and loses the ability for critical judgement

14. copyright Harry Oxer 5/2003 14 When to use oxygen 10,000’You MUST use it above 10,000’ All the time If oxygen fails, or any doubts, DESCEND ! Fly another day

15. copyright Harry Oxer 5/2003 15 When should I consider oxygen earlier? Anaemia, lung disease, older, heart problems, smoking, hang-over. Cold (Shivering increases O 2 consumption up to 20 times!) Illness Medications?

16. copyright Harry Oxer 5/2003 16 Summary If climbing, commence oxygen by 10,000’ Maintain until well below 10,000’ Check flow and contents often If in doubt about flow, duration, DESCEND! KNOW YOUR EQUIPMENT THOROUGHLY before you fly.

17. Using oxygen for gliding EDS-D1 system

18. copyright Harry Oxer 5/2003 18 Mountain High Oxygen supply

19. copyright Harry Oxer 5/2003 19 EDS-D1 Aviation Oxygen system

20. copyright Harry Oxer 5/2003 20 Using oxygen Check: Cylinder – security, sufficient contents, turned ON Battery in unit and working. Cold reserve? Unit connected to O 2 and to nasal prongs or mask – reachably stowed

21. copyright Harry Oxer 5/2003 21 Using oxygen All settings will automatically give sufficient oxygen – or more – for the flight altitude F 10 settings ADD a flow equivalent to that which you’d get at 10,000’ ‘D’ settings: D 5 - - - O 2 comes on at 5000’ D 10 - - - O 2 comes on at 10,000’ D 12 - - - O 2 comes on at 12,000’ Flow increases automatically with height

22. copyright Harry Oxer 5/2003 22 Press to set Oxygen flow alarm Non- breathing alarm

23. copyright Harry Oxer 5/2003 23 Using oxygen MUST be on by 10,000’ Above 18,000’ FAI recommend full mask rather than just nasal prongs MUST trigger oxygen with each breath – this usually means breathe IN through nose Alarms sound if 45 seconds with no flow – either not sniffing, not breathing, oxygen run out, battery run out.

24. copyright Harry Oxer 5/2003 24

25. copyright Harry Oxer 5/2003 25

26. copyright Harry Oxer 5/2003 26 Press nose clip to fit Pull elastic both sides to snug fit Place elastic below ears Only mask above 18.000 with EDS 1

27. copyright Harry Oxer 5/2003 27 If you wear a beard, a good mask seal is difficult You risk hypoxia at altitude!

28. copyright Harry Oxer 5/2003 28 Using oxygen If alarm sounds, and oxygen not flowing, press to last button position – R/M mode (reserve/manual) – gives half second oxygen pulses (longer) airbrakes, and GET DOWN!

29. copyright Harry Oxer 5/2003 29 Using oxygen - summary Use “D” from 10,000’ If older, chest problems etc. use “F” settings Check and KNOW your Oxygen system It is your LIFE above 10,000’. Harry Oxer