A member has reported an incident in which a low pressure mud hose parted. The incident occurred during the disconnecting and lifting of the mud hose from a vessel to a platform. The mud hose was disconnected from the vessel manifold, and the vessel banksman gave a signal to the crane operator to lower the sling. The hose was attached to the sling and a signal was given to raise the hose. The intent was that the crane should take the weight of the hose and then the securing line from the vessel to the hose could be more easily disconnected. However, the crane operator misunderstood the hand signals and continued to lift whilst the hose was still lashed to the vessel. As a result the coupling and hose parted. As transfer of mud had stopped, there was no spill and there were no injuries.
Our member investigated and noted the following immediate causes of the incident:
- Procedures not understood . the crane operator may not have been aware that the hose was lashed to the vessel;
- There was poor visibility at the time of the incident owing to heavy rain.
The following root causes were identified:
- Communication between workgroups was not effective . poor visibility noted at the time of the incident, and the crane driver may not have seen the stop sign by the banksman. The banksman did not have direct very high frequency (VHF) communication with the crane operator.
The following lessons were learnt:
- There should be clear and continuous radio communication between vessel master and the crane operator and banksman during lifting operations;
- Hand signals can be used provided the banksman can always be clearly seen by the crane operator. In conditions of poor visibility, radio communication between banksman and crane operator should be clear and continuous.
With regard to communications during lifting operations, Members are reminded of IMCA’s guidance on this topic:
IMCA Safety Flashes summarise key safety matters and incidents, allowing lessons to be more easily learnt for the benefit of all. The effectiveness of the IMCA Safety Flash system depends on Members sharing information and so avoiding repeat incidents. Please consider adding email@example.com to your internal distribution list for safety alerts or manually submitting information on incidents you consider may be relevant. All information is anonymised or sanitised, as appropriate.
IMCA’s store terms and conditions (https://www.imca-int.com/legal-notices/terms/) apply to all downloads from IMCA’s website, including this document.
IMCA makes every effort to ensure the accuracy and reliability of the data contained in the documents it publishes, but IMCA shall not be liable for any guidance and/or recommendation and/or statement herein contained. The information contained in this document does not fulfil or replace any individual’s or Member's legal, regulatory or other duties or obligations in respect of their operations. Individuals and Members remain solely responsible for the safe, lawful and proper conduct of their operations.