1. NITROX PRODUCTION WITHIN A DIVE OPERATION
Presented by:
Cesare Benelli,Coltri Sub & Glenn Huebner, Nuvair

2. WHAT IS “NITROX”?
N2O2
Also referred to as EAN, EaNX, Enriched air, & Enriched air nitrox
A gas mixture containing nitrogen & oxygen with a higher % of oxygen than normal breathing air
OEA - Oxygen enriched air

3. WHY DO RECREATIONAL DIVERS USE NITROX?
Less N2 absorption in body tissue.
Lessens risk of decompression sickness.
Provides longer bottom times.
Increases safety margins.
Popular with Dive masters & instructors.

4. WHEN CAN RECREATIONAL DIVERS USE NITROX?
On all recreational dives.
Leading training agencies have introduced optional nitrox training within entry level courses.
Leading training agencies have also introduced introductory programs to initiate divers to nitrox prior qualification

5. WHAT % OF REC DIVERS ARE USING NITROX?
Exact figures not known, but tens of 1000’s of divers train each year with Nitrox
Many dive resorts & liveaboard/charter vessels are already providing nitrox

6. TRAINING REQUIRED FOR THE USE OF NITROX
Courses are available from all
major DSAT agencies
Basic Nitrox training allows diving
with up to 40% mix
Technical Nitrox training is required for mixes over 40%

7. WHY OFFER NITROX ? To increases potential revenue
Provides more & diverse diving opportunities for clients.
Provides additional training opportunities & revenue
Attracts more customers to your dive centre / vessel
Extra equipment sales

8. ADDITIONAL REASONS TO OFFER NITROX.
Reduction of DCS exposure to divers on multi-day dive trips
Reduces operator, Dive master & Instructor liability
Provides a marketing edge over competitors.
Adoption of Nitrox by all major training agencies
Emergence of ‘tech’ diving within the mainstream.

9. WHO ELSE USES NITROX? Recreational dive professionals
Public safety divers
Scientific divers
Commercial divers
NASA astronauts

10. HOW IS NITROX DELIVERED TO THE DIVER?
Specially marked cylinders
Diver must have proof of nitrox certification
Diver must analyze gas
Diver must sign gas log
For ‘Nitrox Experience’ programs Certified DM/Instructors to comply with above procedures.

11. NITROX PRODUCTION OPTIONS:
PARTIAL PRESSURE BLENDING
CONTINUOUS FLOW BLENDING
MEMBRANE SYSTEM

12. PARTIAL PRESSURE BLENDING
Decant 100% pure O2 to dive cylinder **
2. Top off with O2 J grade compatible air **
** Amounts vary according to required mix and cylinder contents & must be calculated.

13. ADVANTAGES OF PARTIAL PRESSURE BLENDING
Lowest start up costs of blending methods.
Popular with technical divers

14. DISADVANTAGES OF PARTIAL PRESSURE BLENDING
Requires transport and handling of 100% pure high pressure O2
Requires error free mathematical calculations
Requires special filtration & expensive consumables to reach J grade quality air.
Requires trained/certified gas blending technician.

15. ADDITIONAL DISADVANTAGES OF P/P BLENDING
Mix may not be exact +/-
P/P blending should be very slow
100% O2 availability
Purchase & transport costs of
100% O2
High levels of liability for operators

16. CONTINUOUS FLOW BLENDING
Gas is pre-mixed using O2 & breathing air with a blending panel
2. Normal high pressure
compressor is used to fill cylinder

17. ADVANTAGES OF CONTINUOUS FLOW BLENDING
Relatively inexpensive
More practical & faster than partial pressure blending
If using an automated blending panel its is an easy to use & precise method. The panel achieves reduction of associated O2 handing risks with the use of auto O2 cut - off valves

18. DISADVANTAGES OF CONTINUOUS FLOW BLENDING
100% O2 availability
Purchase & transport costs of 100% O2
High levels of liability for operators

19. MEMBRANE SYSTEM NITROX PRODUCTION
Normal Air filtered to Grade E standard & pumped into low pressure
O2 permeates thru membrane more than N2 . N2 rich mix vented, O2 rich mix pumped into high pressure compressor **
Normal high pressure compressor used to fill cylinder.
** N2O2 mix controlled via air flow rate into membrane.

20. POSSIBLE MEMBRANE SYSTEMS
LP compressor - LP filtration - Membrane - HP compressor - cylinder

21. POSSIBLE MEMBRANE SYSTEMS
Air bank - LP pressure reducer - LP filtration - Membrane - HP compressor - Cylinder

22. ADVANTAGES OF A MEMBRANE SYSTEM
Simple operation
No need to store or mix high-pressure O2
Virtually eliminates hazards associated with handling 100% O2
Highly accurate method of blending

23. ADDITIONAL ADVANTAGES OF MEMBRANE SYSTEMS
FAST: Fill nitrox tanks at same speed you fill with air
LOW: Maintenance & operating costs.
SIMPLE: Training & use.
Note: Membrane systems have the lowest levels of
Operator risk exposure when filling Nitrox cylinders.

24. RELIABILITY OF THE COLTRI /NUVAIR MEMBRANE
Systems reliable as a normal air compressor systems
20-30 year life span
Compressor are covered by 1 year warranty
Membrane systems are covered by 5 year warranty.
Note: It is Important stated maintenance procedures are followed

25. DISADVANTAGES OF A MEMBRANE SYSTEM?
Higher initial capital investment
May require additional electrical power

26. IS A NEW HP COMPRESSOR NEEDED FOR NITROX?
Can usually use your existing compressor .
A well maintained ‘used’ compressor may need a mild overhaul and internal cleanup if previously used with mineral oil.**
** Any HP Compressor used to compress Nitrox must be lubricated by a synthetic oil rated for use with nitrox

27. IS USING NITROX WITH A HP COMPRESSOR SAFE?
There are attendant risks with compressing any gas
Compressing N2O2 containing 40% or less O2 poses no more risk than pumping normal breathing air at higher pressures

28. WHEN USING MEMBRANE OR CONTINUOUS BLENDING…
Considerations:
Slightly more conservative than compressing air
Compressor oil
Compressor operating temp.
Filtration

29. WHAT IF I NEED TO PRODUCE 40%+ NITROX MIX?
Recreational Divers will not use more than 40% Nitrox
The most popular mix currently used within dive centers/vessels is 32%
If a deco mix exceeding 40% is required by tech divers a P/P system can be used.
Note: Recommended depth limit for recreational divers is 30m, best suited to a 32% Nitrox mix

30. TRAINING STAFF TO FILL NITROX TANKS
Most people can learn to operate a membrane nitrox system in less than one hour.
We will be conducting a live demonstration at the end of this session

31. END OF PART ONE