optional, single

—

Inside the <gasdefinitions> section happens the definition of the different breathing gases used by the <owner> of the UDDF file.

<gasdefinitions> stands after the <divesite> section and before <profiledata>.

The only element inside <gasdefinitions> is <mix> which can be repeated any times.

The <gasdefinitions> section can be omitted. If <gasdefinitions> doesn't occur, the executing software has to set air as the breathing gas to be used. Of course, a breathing gas consumption calculation cannot be performed in case of a missing <gasdefinitions> section.

<uddf>

<mix>

<mix>, <tankdata>

<gasdefinitions>
    <!-- all breathing gases used -->
    <mix id="oxygen_pure">
        <name>pure oxygen</name>
        <o2>1.000</o2>
        <n2>0.000</n2>
        <he>0.000</he>
        <ar>0.000</ar>
        <h2>0.000</h2>
    </mix>
    <mix id="air">
        <name>air</name>
        <o2>0.210</o2>
        <n2>0.790</n2>
        <he>0.000</he>
        <ar>0.000</ar>
        <h2>0.000</h2>
    </mix>
    <mix id="nitrox6040">
        <name>Nitrox60/40</name>  <!-- Nitrox 60 % N2, 40 % O2 -->
        <o2>0.400</o2>
        <n2>0.600</n2>
        <he>0.000</he>
        <ar>0.000</ar>
        <h2>0.000</h2>
    </mix>
    <mix id="trimix">
        <name>Trimix</name>  <!-- Trimix 15 % O2, 40 % N2, 45 % He -->
        <o2>0.150</o2>
        <n2>0.400</n2>
        <he>0.450</he>
        <ar>0.000</ar>
        <h2>0.000</h2>
    </mix>
</gasdefinitions>