SUUNTO Vyper Air - Manual (Page 74)

6.2. Diving in NITROX mode (DIVE Nitrox)
The NITROX mode (DIVE Nitrox) is the second dive mode available in Suunto Vyper
Air and is used when using oxygen-enriched gas mixtures.
6.2.1. Before diving in the NITROX mode
If set to the NITROX mode, the correct oxygen percentage of the gas in your cylinder
must always be entered into the computer to ensure correct nitrogen and oxygen
calculations. The dive computer adjusts its mathematical nitrogen and oxygen calcu-
lation models accordingly. The dive computer will not accept fractional percentage
values of oxygen concentration. Do not round up fractional percentages. For example,
31.8% oxygen should be entered as 31%. Rounding up will cause nitrogen percentages
to be understated and will affect decompression calculations. If you want to adjust the
computer to provide more conservative calculations, use the personal adjustment
feature to affect decompression calculations, or reduce the PO
2
setting to affect oxygen
exposure according to the entered O
2
% and PO
2
values. Calculations based on nitrox
use result in longer no-decompression times and shallower maximum depths than
diving with air.
As a safety precaution, the oxygen calculations in the computer are made with an
oxygen percentage of 1% + set O
2
%.
When the dive computer is set in NITROX mode, the Dive Planning mode calculates
using the O
2
% and PO
2
values that are currently in the computer.
To set the nitrox mixes, refer to Section 5.7.3. Setting the nitrox values .
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