The Accident Investigation Board Norway (AIBN) has recommended that the Norwegian Maritime Authority (NA) carry out an assessment of whether its current regulatory framework is sufficient to ensure safety on board offshore vessels that are engaged in complex national and international operations for the petroleum industry.
The recommendation comes in AIBN’s report on an explosion on board the construction service vessel Normand Maximus (IMO 9744518) on February 21st 2017 off Rio de Janeiro, Brazil.
One person died and four were injured. The ship was used in a pre-commissioning operation on an oil field.
AIBN noted that the regulatory framework for ships did not contain requirements that covered the type of operation for which Normand Maximus was used.
Normand Maximus was hired by oil industry service company Saipem and was to function as a platform at sea for the duration of the assignment. In cooperation with oil industry service company Baker Hughes, Saipem was to carry out pre-commissioning (tests to verify that all equipment and components were in accordance with the requirements stipulated) for Brazilian state-owned oil company Petrobras on the oil field Lula. Baker Hughes was conducting pressure testing of the oilfield’s gas flow system when the accident happened.
The pressure testing operation took place in a cordoned off area on the CSV Normand Maximus’s open aft deck. A permit to work (PTW) system was used to identify hazards and ensure that safety measures were implemented.
At 06:15 on Tuesday February 21st 2017, in connection with recovery/depressurisation of the MEG1 system, at a pressure of 215 bar, the compressed mixture of air and MEG exploded, which resulted in several blowouts and breaks in the system of pipes and valves on the open deck.
A Baker Hughes employee who was working in front of a manual pipe valve was hit by the valve’s handwheel, which was thrown out by the explosion, and died as a result. One seriously injured person and three persons with minor injuries were found on the deck.
CSV Normand Maximus was deemed to have been a vessel when it was hired and used by Saipem in the pre-commissioning operation. Therefore, the regulatory framework governing ships applied to the CSV Normand Maximus during this operation. No independent party checked or approved whether the functionality of the completed installation was satisfactory for use on board the vessel after the equipment had been installed on deck and was ready for use on the oil field.
AIBN said that an independent check and approval by an external party would have probably have contributed to the shipping company/vessel being more confident in the performance of their duties as the party responsible for safety on board the vessel. AIBN has submitted a safety recommendation to the Norwegian Maritime Authority (NMA) on this point.
The Brazilian Navy also conducted an investigation into the incident. It found that there was inadequate monitoring and control at different points in the system, including temperature monitoring. It said that the use of a manually actuated flow control and depressurising valve was the determining factor for the death of the worker, since his positioning in the operation was frontal to the valve and, when it exploded, he was directly hit by the steering wheel of equipment. The Navy concluded that, for this type of system, equipment with remote actuation should be used.
The Brazilian Navy also found several broken pipes, torn hoses and faulty locking and relief valves. The installation was without supports, grounding measures were inadequate, there were loose fixtures and some temperature loggers were not installed.