Via <globalalarm> a so-called "global" alarm given by the dive computer is put into brackets. Such alarms are given only once during a dive and affect this whole dive. In contrast to "normal" alarms, normally given multiple times (by means of occurence in direct following <waypoint>s), and which are only temporary events, "global" alarms are not stored inside the <samples> section but in <globalalarmsgiven>.
At time the following global alarms with these keaywords are supported:
ascent-warning-too-long — ascent velocity too high and/or decompression stops disregarded
sos-mode — dive computer is locked
work-too-hard — load of physical effort too high for a prolonged time
attribute "alarm" of <waypoint>, <globalalarmsgiven>