Diver reports unwell post-dive: non-decompression illness
- Safety Flash
- Published on 14 August 2025
- Generated on 22 May 2026
- IMCA SF 14/25
- 2 minute read
A diver experienced a dizzy spell about one hour after completing a diving operation
What happened?
The incident occurred after the 50 year old diver undertook a dive to 87 feet with a bottom time of 31 minutes. The diver was decompressed on a USN rev 7. 90/33 'freetime dive’ and reported well upon surfacing. About one hour later, on deck, the diver called out for attention reporting extreme nausea and dizziness.
What was the response?
The diver was immediately recompressed in the chamber on a USN treatment table 6 as per company procedure with a Diver Medic Technician (DMT) with him in attendance. The DMT performed a full physiological and neurological examination and blood sugar levels were taken as a precautionary measure. The diver’s blood sugar levels were observed to be dangerously high.
A hyperbaric physician was contacted and following their advice, decompression illness was ruled out and hyperglycaemia was suspected, as the examination pointed towards a diabetic response. Treatment table was switched to a Table 5 to reduce chamber time so that the diver could have his blood sugar levels brought under control at the earliest opportunity.
After 90 minutes the diver and DMT were able to leave the chamber. The diver was evacuated ashore for further medical attention.
What was the problem?
It was later reported that the diver had an unreported diabetic condition for which he was not taking any traditional therapy but was seeking alternative natural methods.
What were the recommendations?
- Healthy eating ‘campaign offshore’ & Welfare Improvement
- Crew should engage with vessel medics for nutritional advice.
- Crew should be motivated to declare medical issues before coming offshore.
- Crew need to be confident that their jobs are not at risk because of declaring their medical conditions.
- Improve crew education on common non-communicable diseases like Diabetes and Hypertension so that they can easily spot when they have symptoms.
- Encourage use of gym when offshore – physical and mental fitness needs to be encouraged and looked after.
- Look closely at ensuring how divers maintain their fitness and Body Mass Index (BMI) to an acceptable level.
Members may wish to refer to:
· IMCA D061 Guidance on health, fitness and medical issues in diving operations
· IMCA HSS033 Guidance on occupational health
Related Safety Flashes
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IMCA SF 04/15
20 March 2015
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