What Is
Nitrox?
 Nitrox is any mixture of Oxygen and Nitrogen.
As such, the air we breathe fits this definition. In diving, and in this course, we will
limit our consideration to those mixtures that have a greater percentage of Oxygen than
the air we breathe. These mixtures are referred to as Enriched
Air Nitrox or, the abbreviation, EANx.
Nitrox I (NI)
and Nitrox II (NII)
are popular mixtures for diving. The modern terms for these mixtures are EANx32 and EANx36.
| Definitions |
| |
Air |
NI
or
EANx32 |
NII
or
EANx36 |
EANx40 |
Pure
Oxygen |
Oxygen
% |
21% |
32% |
36% |
40% |
100% |
Nitrogen
% |
79% |
68% |
64% |
60% |
0% |
The tolerance on NI and NII is + or - 1%. Thus
EANx31 to EANx33 is considered to be NI and EANx35 to EANx37 is considered to be NII.
All Nitrox mixtures are odorless
and tasteless. This is good, because it
means that you will not have to get used to new odors or tastes. The downside is that you
can not use your senses of smell and taste to tell one mixture from another. To your
senses, they all seem the same.
Note: While the focus in this course is on the amount of Oxygen in the mixture, the real
benefits of Nitrox come from the reduced Nitrogen content of the mixture. Thus, you might
do better to think of Nitrox, not as Oxygen enriched air, but rather, as Nitrogen reduced
air.
|
