The Bahamas Maritime Authority issued this Safety Alert to share lessons learned from a fatal incident involving the improper storage of dry ice aboard a vessel during a maintenance period. The information is based on findings from a preliminary investigation.
What Happened
A drill ship undergoing extended maintenance required dry ice to complete disassembly work on drilling equipment. A subcontractor supplied approximately 300 kg of dry ice in 20 unmarked insulated boxes. The boxes were delivered onboard three days before use and stored in a cold room. On the evening before the scheduled work, a service technician was discovered seated and unresponsive inside the cold room, showing no signs of injury or struggle. The emergency door release and entrapment alarm were functional but had not been activated, and lighting in the cold room was operational. Other crew members had entered the room about an hour earlier and did not experience any ill effects. The vessel’s medical officer initially suspected natural causes, with post-mortem results pending.
Why It Happened
The incident occurred due to the accumulation of carbon dioxide gas released from sublimating dry ice that had been stored in an enclosed, poorly ventilated cold room. Dry ice, which is solid carbon dioxide, sublimates directly into gas at temperatures above -78°C. This gas is heavier than air and can quickly displace oxygen in confined spaces, creating an oxygen-deficient and life-threatening atmosphere. In this case, approximately 300 kg of dry ice was stored in 20 insulated, unmarked boxes without proper ventilation or hazard identification. No risk assessment was conducted before bringing the dry ice onboard, and the crew was not aware of the potential asphyxiation hazard. The lack of warning labels or safety data information further contributed to the unrecognized risk. As the dry ice gradually sublimated, the carbon dioxide concentration in the cold room likely increased to dangerous levels, resulting in a fatal environment for anyone entering the space.
Actions Taken
The alert emphasizes the need for clear labeling of dry ice packaging and the inclusion of Material Safety Data Sheets (MSDS) when supplied. It also underscores the requirement to conduct risk assessments and ensure adequate ventilation for all dry ice storage areas.
Lessons Learned
- Always store dry ice in well-ventilated spaces to prevent CO₂ accumulation.
- Label and communicate hazards clearly on packaging and through MSDS.
- Assess risks before handling or storing dry ice onboard any vessel.
- Recognize that normally safe spaces can become hazardous if filled with sublimated CO₂.
- Maintain crew awareness and training regarding asphyxiation risks in enclosed or refrigerated areas.
Did you subscribe to our Daily newsletter?
It’s Free! Click here to Subscribe!
Source: Bahamas Maritime Authority
