How to Set a Dive Computer for Nitrox
- 1). Hold the oxygen analyzer up to the valve on the nitrox tank and open the valve very slightly so that a small flow of gas is escaping the tank. Ensure that the stream of gas from the tank is pointing directly into the input of the oxygen analyzer.
- 2). Wait for the numbers on the oxygen analyzer to stabilize. Read the number (the percentage of oxygen in the mixture) and write it on the tank for reference. This is the FO2 or fraction of oxygen in the mixture.
- 3). Turn on the dive computer and scroll through the menu to find the FO2 or %O2 option. This option varies based upon the computer being used.
- 4). Scroll up or down to set the FO2 to match the FO2 written on the tank (from Step 2.)
- 5). Scroll the menu to the PO2 option and set it to 1.4 (conservative safe level) or 1.6 (maximum recommended safe PO2 level.)
- 6). Accept all settings to lock them into the computer for the upcoming dive.
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