We have discussed the hazards and risks associated with the transferring of hazardous materials in bulk. This case was a terminal to ship transfer, but these basic failures can happen on any transfer. Not following procedures, not utilizing an unloading checklist, and not using the unloading process and the nitrogen purge process as it was DESIGNED all led to this OVER PRESSURE EVENT involving a Category 2 flammable liquid with damages near $1,000,000.
On May 30, 2019, about 0750, a chemical tanker ship experienced an overpressurization of the number 3 port and starboard cargo tanks while discharging liquid hexene at Vopak Terminal in Deer Park, Texas. The overpressurization resulted in damage to the number 3 port cargo tank and the tank top (deck). All cargo was contained onboard the double-hulled vessel, with no pollution or injuries reported.
Damage to the ship was estimated at $750,000, and the contaminated cargo was an estimated $100,000 loss.
The National Transportation Safety Board (NTSB) determines that the probable cause of the overpressurization and rupture of the 3P cargo tank aboard the Fairchem Filly during offloading was the VESSEL AND TERMINAL PERSONNEL INVOLVED NOT FOLLOWING POLICIES AND PROCEDURES RELATED TO CARGO DISCHARGE AND NITROGEN-BLANKETING OPERATIONS. Contributing to the casualty was the lack of effective communication between the vessel and terminal personnel and the decision of the vessel’s PIC to continue discharge operations after being unable to communicate with the terminal.