Transporting coconut oil and its derivatives by sea carries a critical yet underestimated risk: the generation of toxic gas inside vessel cargo tanks. Manish Nayyar, Senior Loss Prevention Executive at NorthStandard, highlights that vegetable oils, particularly Crude Coconut Oil (CCNO) and Coconut Fatty Acid Distillate (CFAD), pose substantial atmospheric hazards in enclosed spaces. Due to its higher impurity levels and lower thermal stability, CCNO can release carbon monoxide (CO)—a colorless, odorless and potentially lethal gas—when heated or agitated.
In the first incident at Rotterdam, two crew members entered a cargo oil tank to perform squeezing operations during routine CCNO discharge. Although pre-entry test readings indicated the tank was safe (recording oxygen levels of 20.9% and virtually zero CO), cargo circulation resulted in visible vapors forming. The pumpman's gas detector alarm activated, but he lost consciousness before evacuating the tank, and both crew members were hospitalized. Subsequent testing revealed alarming CO levels of 400ppm. During a CFAD discharge operation at Lianyungang, China, five crew members entered a cargo tank without conducting proper atmospheric testing or following enclosed space entry procedures. All five collapsed due to toxic gas exposure, and four died.
These accidents were foreseeable due to repeated procedural failures. Ship staff failed to identify the release of hazardous vapors during cargo circulation, while pre-entry risk evaluations proved inadequate. Both incidents were compounded by communication breakdowns; the Cargo Control Room (CCR) was not informed that personnel were still inside the tank. The affected personnel had limited understanding of the specific toxic vapor hazards of coconut oil products, the impact of cargo movement on enclosed space atmospheres, and that initial safe readings do not ensure continued safety.
The tanker industry must implement measures to prevent similar incidents. One crucial safety measure is prohibiting any cargo movement while personnel are inside cargo tanks unless authorized through a dedicated, documented risk assessment. Before entry, crew must conduct enhanced, multi-point testing at the top, middle and bottom of the tank from multiple access points. Where vegetable oils are involved, at least four hours should be allocated to ventilation, and oxygen levels should be verified at/above 20.9% with toxic gases (including CO) at 0ppm. After entry, personnel inside the tank must maintain atmospheric monitoring at intervals of no more than 15 minutes, using extended sampling tubes to check atmosphere at multiple levels and set conservative alarm thresholds.
Large cargo tanks carrying coconut oil products require multiple ventilation points; a single portable blower is inadequate. Communication protocols must be strengthened, with the CCR using closed-loop communication and obtaining explicit "all personnel clear" confirmation before starting any cargo operations. Temperature management is also crucial; heating temperatures in cargo tanks should be kept at minimum necessary levels to maintain cargo fluidity while avoiding hazards and rapid temperature changes.
Key Takeaways:
1. Crude coconut oil (CCNO) can release carbon monoxide (CO), a colorless and odorless lethal gas, when heated or agitated.
2. Two recent incidents at Rotterdam and Lianyungang ports resulted in five deaths and exposed procedural failures.
3. Pre-entry safe readings do not guarantee continuous safety as cargo movement can release trapped gases.
4. Personnel must not remain inside tanks during cargo operations, and multi-point atmospheric testing is required.
5. Atmospheric monitoring every 15 minutes inside tanks and regular communication with Cargo Control Room are mandatory safety measures.
