Document ID: chunk:federal_register_of_legislation:F2023L00464:reg:9
Version: federal_register_of_legislation:F2023L00464
Segment Type: reg
Provision Reference: reg 9
Character Range: 3695–6513

9               Factors that must exist
At least one of the following factors must as a minimum exist before it can be said that a reasonable hypothesis has been raised connecting decompression illness or death from decompression illness with the circumstances of a person's relevant service:
(1)          experiencing a substantial episode of decompression whilst:
(a)          surfacing from an underwater dive that required decompression stops according to relevant diving decompression tables;
(b)          flying at >5,486 metres (>18,000 feet) altitude in an unpressurised aircraft, high altitude balloon or high altitude parachute;
(c)          flying, parachuting or ballooning within the no flying time interval after underwater diving, where the relevant diving decompression tables recommended a no flying time interval;
(d)          ascending to the surface from a submerged submarine or vessel at >90 metres seawater (296 feet seawater) with a normal internal pressure, or ascending to the surface from a submerged submarine or vessel at increased internal pressure;
(e)          suffering loss of cabin pressure in an aircraft flying at >5,486 metres (>18,000 feet) altitude or in a spacecraft above the von Karman line;
(f)           returning to surface air pressure after working in a hyperbaric compressed air environment including working in a tunnel, caisson or tunnel boring machine;
(g)          transferring from a higher pressure to a lower pressure environment whilst in space including donning an extravehicular space suit;
(h)          being in a hypobaric chamber;
(i)            returning to surface air pressure after being in a hyperbaric chamber including hyperbaric oxygen therapy chambers; or
(j)            returning to surface air pressure after being within a pressure vessel during hyperbaric pressure testing including aircraft cabin excessive leak testing, submarine pressure testing, and nuclear power station pressure testing;
within 7 days before the clinical onset of decompression illness;
Note 1: Substantial episodes of decompression involves a rapid substantial reduction in the ambient pressure exerted by the envelope of gas or water surrounding the person where the person had been at higher pressure for a substantial period.
Note 2: Underwater diving includes breath hold diving, yo-yo or bounce diving, umbilical/hookah/hard hat diving, SCUBA diving, rebreather diving, and saturation diving. This underwater diving does not including diving within normobaric diving bells or armoured suits.
Note 3: A decompression stop is a procedure where the diver is required to stop at a specified depth for a specified time interval to allow the inert gas to clear from their body.
(2)          inability to obtain appropriate clinical management for decompression illness.