The <alarm> element indicates the type of alarm the dive computer gives at a <waypoint>. Several <alarm> elements may appear inside a <waypoint> element, one for each reason of alarm respectively.
At time the following keywords are recognised:
    keyword          announcement of dive computer
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    rbt              remaining bottom time exceeded
    error            general error (deco stop missed, etc.)
    ascent           ascent too fast
    deco             announcement of a deco stop
    breath           breathing frequency too high
    surface          surface reached
                <waypoint>
<waypoint>