Proceedings magazine is a communication tool for the Coast Guard's Marine Safety & Security Council. Each quarterly magazine focuses on a specific theme of interest to the marine industry.
Issue link: http://uscgproceedings.epubxp.com/i/707823
70 Proceedings Summer 2016 www.uscg.mil/proceedings revolutions per minute. These vapors most likely powered the engines after the crew manually shut off the fuel supply. Allowing the towing vessel to pull up and moor at the facility in such close prox- imity to the tank cleaning operations introduced an ignition source to an atmosphere with an already- high concentration of flammable vapors. Environmental factors also contributed to this inci- dent. During the day and evening of the event, the wind speeds were calm to almost nonexistent. These conditions — coupled with the tank cleaning employees' failure to employ proper tank ventila- tion procedures, the ensuing failure of the mechani- cal blowers, and the flammable vapors generated during the tank cleaning operations — created a hazardous accu- mulation of flammable vapors on the deck and in the cargo tanks of the two barges, on the water's surface, and at the facility. The tank cleaning operation employees were not prop- erly qualified to do the job. Investigators found that the employees working at the facility, including the person in charge, did not hold a tankerman-PIC endorsement on a Coast Guard merchant mariner's credential. Therefore, the company's failures to hire and train employ- ees with the correct certifications and knowledge resulted in the extensive release of flammable vapors. The resultant explosion and fire caused subsequent injury to the three workers, and contributed to the total destructive loss of two tank barges. Acknowledgments: Proceedings would like to thank CDR Scott W. Muller, chief of the Inspection and Investigation Branch at U.S. Coast Guard District 5; and Mr. Ken Olsen, Office of Investigations and Analysis at USCG headquarters, for contributing to this story. About the author: Ms. Sarah K. Webster is a public affairs specialist at the Bureau of Reclama- tion. She was previously the managing editor of the USCG Proceedings of the Marine Safety & Security Council magazine, a beat reporter for Micromedia Publications, and a news reporter and feature writer for Gannett Company, Inc. She has an M.A. in communication from Kent State University, a B.A. in communication from Monmouth University, and an A.A. in humanities from Ocean County College. Endnote: 1. The description of procedures for tank cleaning and stripping operations required by 33 CFR §154.310 (a) (23) states: "Tank cleaning and stripping will be done in accor- dance with the International Safety Guide for Oil Tankers & Terminals, ISGOTT, Chap- ter 9. (Appendix 6)." gas freeing operations, and failed to develop and enforce appropriate tank cleaning procedures consistent with Coast Guard regulations and best practices. The company also failed to: • provide properly trained and qualified oversight, • conduct cargo line and bottom flushing with water before commencing forced ventilation, • monitor for flammable vapors, • use effective ventilation procedures, • prevent the introduction of ignition sources, including allowing for other vessels to berth at its facility. Lessons Learned Failing to use water to first flush and strip the cargo pipes and tank bottoms of residual cargo before ventilating the tanks allowed an unsafe concentration of flammable vapors into the atmosphere. The concentration level of flammable vapors was so high that, when the vapors were absorbed into the approaching towing vessel's engine air intakes, this actually introduced additional fuel to speed up the engine's Views of the two damaged tank barges from the starboard stern.