Voyager IV
Nitrox System
Nuvair www.nuvair.com
Page
36
Appendix
Supply and Breathing Air Specifications
All supply and breathing air must meet the following requirements of CGA G-7.1-1997. Supply air
delivered to the Membrane System must be purified to meet Grade D or E quality, and periodic air
quality testing to assure compliance is recommended. All breathing air for diving produced by the
downstream Compressor must be purified to meet Grade E quality, and periodic air quality testing to
assure compliance is mandatory.
Item
Grade D
Grade E
Oxygen
19.5-23.5%
20-22%
Carbon Dioxide (maximum)
1000 PPM
1000 PPM
Carbon Monoxide (maximum)
10 PPM
10 PPM
Hydrocarbons (maximum)
Not specified
25 PPM
Water Vapor (maximum)
Not specified
Not specified
Dew Point (maximum) (1)
Not specified
Not specified
Oil & Particles (maximum) (2)
5 mg/m3
5 mg/m3
Odor
None
None
Notes: (1) Dew Point of supply air must be >10
o
F (6
o
C) colder than coldest ambient air expected
(2) Supply air delivered to the Membrane System must contain <0.003 PPM Oil Vapor
All breathing Nitrox produced for diving must be purified to meet these same requirements, except for
oxygen content. Nitrox oxygen content must measure /- 1% O
2
of the specified value of the
mixture using a properly calibrated Oxygen Analyzer (i.e. Nitrox produced with a target content of
32% O
2
must measure in the range of 31-33% O
2
). Periodic air quality testing to assure compliance
is mandatory.
Filter Element Life Factors
Breathing air filter element life is typically rated by manufacturer based on an air temperature of 80ºF
at the filter inlet. Under normal operation this temperature is 12ºF (5ºC) warmer than the ambient air,
resulting in an equivalent ambient temperature rating at 68ºF (20ºC).
To determine element life at a different ambient temperature, multiply the rated life by the life factor
listed below:
Filter
Temperature
Ambient
Temperature
Filter Element
Life Factor
53ºF (12ºC)
41ºF (5ºC)
2.6 x Life
62ºF (17ºC)
50ºF (10ºC)
1.8 x Life
71ºF (23ºC)
59ºF (16ºC)
1.35 x Life
80ºF (27ºC)
68ºF (20ºC)
1 x Life
89ºF (32ºC)
77ºF (25ºC)
0.8 x Life
96ºF (36ºC)
84ºF (29ºC)
0.55 x Life
105ºF (41ºC)
93ºF (34ºC)
0.45 x Life
114ºF (46ºC)
102ºF (39ºC)
0.35 x Life
