A PSV was working alongside an installation and had successfully completed a discharge of oil based mud (OBM) to the installation via the mud hose. The vessel was subsequently required to deliver base oil (BO) using the same (OBM) delivery hose.
In order for the hose to reach the BO manifold onboard, the vessel would be required to re-position the OBM hose from the forward hang off pin to the aft hang off pin. This was to be executed utilising the platforms crane. The OBM hose was connected to the crane pennant and was lifted clear from the forward hang off pin in the usual manner. It was then transferred aft and re-positioned to one of the hang off pins adjacent to the BO connection. Once the hose was in the required position the hang off sling was placed over the pin.
The ABs noticed that the hose hang off sling was displaying signs of wear and tear / damage during the re- positioning of the hose from the forward to the aft pin. They however continued with the operation and as a precautionary measure they decided to secure the hose with a piece of rope as a backup.