biostudies-literatureUnknown55(2)Gouin E<h4>Introduction</h4>The use of gas mixtures containing helium for deep recreational diving is increasingly common, involving complex logistics and decision-making compromises. The characteristics and inherent risks of this practice remain poorly documented. This study aims to provide an epidemiological inventory of practices and diving-related incidents within the technical diving community.<h4>Methods</h4>An international online survey was disseminated on social networks targeting certified trimix divers. It collected demographic data, diving experience, and dive management practices, along with self-reported unusual symptoms, treatments, and outcomes following trimix dives.<h4>Results</h4>A total of 558 questionnaires were analysed, predominantly from males (92%), mostly over 46 years oDiving and hyperbaric medicine114-125https://www.ebi.ac.uk/biostudies/studies/S-EPMC12267066biostudies-literatureDiving practices in technical divers' community and behaviour towards self-reported unusual symptoms.PMC12267066Gouin EBlatteau JEMichot TMonnot DPGuerrero FfalseDiving practices in technical divers' community and behaviour towards self-reported unusual symptoms.<h4>Introduction</h4>The use of gas mixtures containing helium for deep recreational diving is increasingly common, involving complex logistics and decision-making compromises. The characteristics and inherent risks of this practice remain poorly documented. This study aims to provide an epidemiological inventory of practices and diving-related incidents within the technical diving community.<h4>Methods</h4>An international online survey was disseminated on social networks targeting certified trimix divers. It collected demographic data, diving experience, and dive management practices, along with self-reported unusual symptoms, treatments, and outcomes following trimix dives.<h4>Results</h4>A total of 558 questionnaires were analysed, predominantly from males (92%), mostly over 46 years o2025-01-01T00:00:00Z2025 Jun2026-03-16T01:21:43.662Z2025-08-14T03:05:26.143ZS-EPMC122670664054413910.28920/dhm55.2.114-125