{"id":"F2023L00465","name":"Statement of Principles concerning decompression illness (Balance of Probabilities) (No. 24 of 2023)","slug":"statement-of-principles-concerning-decompression-illness-balance-of-probabilities-no-24-of-2023","collection":"legislative_instrument","jurisdiction":"commonwealth","status":"in_force","isInForce":true,"actNumber":null,"makingDate":null,"administeringDepartment":null,"currentVersion":{"id":441811,"registerId":"F2023L00465-fast-fetch-1775957014329","compilationNumber":null,"startDate":"2026-04-12","status":"InForce","reasons":null,"registeredAt":null},"sections":[{"sectionNumber":"1","sectionType":"section","heading":"Statement of Principles concerning decompression illness (Balance of Probabilities) (No. 24 of 2023)","content":"---\nmeta-content-style-type: text/css\nmeta-content-type: application/xhtml+xml; charset=utf-8\nmeta-generator: Aspose.Words for .NET 22.10.0\n---\n\n?xml version=\"1.0\" encoding=\"utf-8\" standalone=\"no\"?>\n\n\n\n \n\nStatement of Principles\n\nconcerning\n\nDECOMPRESSION ILLNESS (Balance of Probabilities)\n\n(No. 24 of 2023)\n\nThe Repatriation Medical Authority determines the following Statement of Principles under subsection 196B(3) of the Veterans' Entitlements Act 1986.\n\n \n\nDated 24 April 2023.\n\n \n\n \n\n \n\n \n\n \n\n| The Common Seal of the Repatriation Medical Authority was affixed to this instrument at the direction of:
|\n| --- |\n|
Professor Terence Campbell AM
Chairperson
|\n\n\n \n\n \n\n\nContents\n\n1 Name\n\n2 Commencement\n\n3 Authority\n\n4 Repeal\n\n5 Application\n\n6 Definitions\n\n7 Kind of injury, disease or death to which this Statement of Principles relates\n\n8 Basis for determining the factors\n\n9 Factors that must exist\n\n10 Relationship to service\n\n11 Factors referring to an injury or disease covered by another Statement of Principles\n\nSchedule 1 - Dictionary\n\n1 Definitions\n\n \n\n\n\n\n1 Name\n\nThis is the Statement of Principles concerning decompression illness (Balance of Probabilities) (No. 24 of 2023).\n\n2 Commencement\n\n This instrument commences on 23 May 2023.\n\n3 Authority\n\nThis instrument is made under subsection 196B(3) of the Veterans' Entitlements Act 1986.\n\n4 Repeal\n\nThe Statement of Principles concerning decompression sickness No. 14 of 2015 (Federal Register of Legislation No. F2014L01832) made under subsection 196B(3) of the VEA is repealed.\n\n5 Application\n\nThis instrument applies to a claim to which section 120B of the VEA or section 339 of the Military Rehabilitation and Compensation Act 2004 applies.\n\n6 Definitions\n\nThe terms defined in the Schedule 1 - Dictionary have the meaning given when used in this instrument.\n\n7 Kind of injury, disease or death to which this Statement of Principles relates\n\n(1) This Statement of Principles is about decompression illness and death from decompression illness.\n\nMeaning of decompression illness\n\n(2) For the purposes of this Statement of Principles, decompression illness:\n\n(a) means an injury caused by the formation of bubbles of nitrogen and other inert gases within tissues and blood vessels, as a result of a reduction in the pressure surrounding the person, and;\n\n(b) includes:\n\n(i) arterial gas embolism not due to pulmonary barotrauma; and\n\n(ii) decompression sickness; and\n\n(c) excludes:\n\n(i) altitude illness;\n\n(ii) arterial gas embolism due to pulmonary barotrauma;\n\n(iii) barotrauma;\n\n(iv) ebullism;\n\n(v) osteonecrosis;\n\n(vi) high pressure neurological syndrome/inert gas narcosis; and\n\n(vii) cerebrovascular accident not due to an arterial gas embolism.\n\nNote 1: Clinical manifestation of decompression illness includes musculoskeletal, cutaneous, lymphatic, cardiopulmonary, inner ear or neurological signs or symptoms.\n\nNote 2: Inert gases include nitrogen, argon, helium, xenon and krypton.\n\nDeath from decompression illness\n\n(3) For the purposes of this Statement of Principles, decompression illness, in relation to a person, includes death from a terminal event or condition that was contributed to by the person's decompression illness.\n\nNote: terminal event is defined in the Schedule 1 – Dictionary.\n\n8 Basis for determining the factors\n\nOn the sound medical‑scientific evidence available, the Repatriation Medical Authority is of the view that it is more probable than not that decompression illness and death from decompression illness can be related to relevant service rendered by veterans or members of the Forces under the VEA, or members under the MRCA.\n\nNote: MRCA, relevant service and VEA are defined in the Schedule 1 – Dictionary.\n\n9 Factors that must exist\n\nAt least one of the following factors must exist before it can be said that, on the balance of probabilities, decompression illness or death from decompression illness is connected with the circumstances of a person's relevant service:\n\n(1) experiencing a substantial episode of decompression whilst:\n\n(a) surfacing from an underwater dive that required decompression stops according to relevant diving decompression tables;\n\n(b) flying at >5,486 metres (>18,000 feet) altitude in an unpressurised aircraft, high altitude balloon or high altitude parachute;\n\n(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;\n\n(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;\n\n(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;\n\n(f) returning to surface air pressure after working in a hyperbaric compressed air environment including working in a tunnel, caisson or tunnel boring machine;\n\n(g) transferring from a higher pressure to a lower pressure environment whilst in space including donning an extravehicular space suit;\n\n(h) being in a hypobaric chamber;\n\n(i) returning to surface air pressure after being in a hyperbaric chamber including hyperbaric oxygen therapy chambers; or\n\n(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;\n\nwithin 7 days before the clinical onset of decompression illness;\n\nNote 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.\n\nNote 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.\n\nNote 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.\n\n(2) inability to obtain appropriate clinical management for decompression illness.\n\n10 Relationship to service\n\n(1) The existence in a person of any factor referred to in section 9, must be related to the relevant service rendered by the person.\n\n(2) The factor set out in subsection 9(2) applies only to material contribution to, or aggravation of, decompression illness where the person's decompression illness was suffered or contracted before or during (but did not arise out of) the person's relevant service.\n\n11 Factors referring to an injury or disease covered by another Statement of Principles\n\nIn this Statement of Principles:\n\n(1) if a factor referred to in section 9 applies in relation to a person; and\n\n(2) that factor refers to an injury or disease in respect of which a Statement of Principles has been determined under subsection 196B(3) of the VEA;\n\nthen the factors in that Statement of Principles apply in accordance with the terms of that Statement of Principles as in force from time to time.\n\n \n\n \n\nSchedule 1 - Dictionary \n\nNote: See Section 6\n\n1 Definitions\n\nIn this instrument:\n\n decompression illness—see subsection 7(2).\n\n MRCA means the Military Rehabilitation and Compensation Act 2004.\n\n relevant service means:\n\n(a) eligible war service (other than operational service) under the VEA;\n\n(b) defence service (other than hazardous service and British nuclear test defence service) under the VEA; or\n\n(c) peacetime service under the MRCA.\n\nNote: MRCA and VEA are also defined in the Schedule 1 - Dictionary.\n\n terminal event means the proximate or ultimate cause of death and includes the following:\n\n(a) pneumonia;\n\n(b) respiratory failure;\n\n(c) cardiac arrest;\n\n(d) circulatory failure; or\n\n(e) cessation of brain function.\n\n VEA means the Veterans' Entitlements Act 1986.\n\n \n\n \n","sortOrder":0}],"analysis":{"kimi_summary":{"content_quality":"ok","complexity_score":4,"scope_assessment":{"changed":true,"description":"The original 2015 instrument was limited to 'decompression sickness' — a narrower medical concept primarily associated with diving. This 2023 version expands scope significantly to cover 'decompression illness' broadly, explicitly including arterial gas embolism, altitude-related incidents, submarine operations, space activities (including extravehicular suits), hyperbaric chamber work, and pressure vessel testing. The 7-day temporal window and the specific altitude/depth thresholds represent a material expansion beyond traditional diving medicine into aviation, space, and industrial hyperbaric contexts."},"complexity_factors":["Multiple nested definitions with cross-references (decompression illness defined in s7(2), then referenced in Schedule 1)","10 distinct scenarios in s9(1) with specific technical thresholds (e.g., \">5,486 metres\", \">90 metres seawater\", \"within 7 days\")","7 explicit exclusions from the definition of decompression illness in s7(2)(c)","Conditional logic in s10(2) limiting the application of the 'inability to obtain clinical management' factor to aggravation cases only","Incorporation by reference of other Statements of Principles in s11, creating interdependence with unknown external instruments","Dual statutory framework application (VEA and MRCA) requiring understanding of two different compensation schemes"],"plain_english_summary":"This instrument updates medical criteria for compensating decompression illness for veterans and ADF members, replacing the 2015 statement. It defines qualifying pressure-related exposures and applies the balance-of-probabilities test — typically requiring a qualifying exposure within seven days before symptoms (or lack of timely treatment). It matters because it sets the legal threshold for proving service-related “the bends,” determining access to treatment and compensation."},"flash_summary":{"complexity_score":4,"scope_assessment":{"changed":true,"description":"This instrument expressly repeals the 2015 Statement (s.4) and replaces it with a new Statement that restates definitions, exclusions and the list of qualifying exposure factors (ss.7–11). The source text does not provide a line‑by‑line comparison, but repeal plus the new definitions and factors indicate the applicable scope is changed insofar as the earlier instrument no longer applies."},"complexity_factors":["Technical medical definitions and exclusions for decompression illness (s.7) increase evidentiary complexity for claim assessment.","List of discrete qualifying exposure events and a seven‑day temporal window requires precise event timing and corroboration (s.9).","Cross‑references to other Statements of Principles create interaction effects and transfer of factors where overlapping conditions exist (s.11).","Application limited to claims under VEA and MRCA requires administrators to map service types to \"relevant service\" definitions (s.5; Schedule).","Standard of causation is balance of probabilities underpinned by 'sound medical‑scientific evidence', placing burden on medical evidence quality (s.8).","Repeal of the 2015 Statement means decision‑makers must apply the new text and disregard the prior instrument (s.4).","Provision for inability to obtain appropriate clinical management as a standalone factor adds non‑medical evidentiary burdens (s.9(2))."],"plain_english_summary":"This instrument defines \"decompression illness\" (what it includes and excludes), sets the medical and service-related factors that must exist for the condition or death to be accepted as connected to a person’s relevant service, and applies to claims under the VEA and MRCA. It repeals the prior 2015 Statement and lists specific qualifying exposures—diving, high‑altitude flight, hyperbaric work, space activity and related events—within seven days before clinical onset as the key triggers for entitlement consideration."},"flash_summary_failed":{"failed":true,"reason":"Unauthenticated. Configure AI_GATEWAY_API_KEY or use a provider module. Learn more: https://ai-sdk.dev/unauthenticated-ai-gateway","source":"analysis-cron"}},"importantCases":[],"_links":{"self":"/api/acts/statement-of-principles-concerning-decompression-illness-balance-of-probabilities-no-24-of-2023","history":"/api/acts/statement-of-principles-concerning-decompression-illness-balance-of-probabilities-no-24-of-2023/history","analysis":"/api/acts/statement-of-principles-concerning-decompression-illness-balance-of-probabilities-no-24-of-2023/analysis","conflicts":"/api/acts/statement-of-principles-concerning-decompression-illness-balance-of-probabilities-no-24-of-2023/conflicts","importantCases":"/api/acts/statement-of-principles-concerning-decompression-illness-balance-of-probabilities-no-24-of-2023/important-cases","documents":"/api/acts/statement-of-principles-concerning-decompression-illness-balance-of-probabilities-no-24-of-2023/documents"}}