Says the alert: “During cargo operations a vessel was passed down a long Oil Based Mud hose with a total of three flotation collars fitted. No concern was raised as to the insufficient quantity of collars and the oil
based mud transfer commenced. During the transfer a large section of the hose became submerged and the position keeping of the vessel allowed for the submerged hose to become entangled in the port propeller.
The vessel returned to port on one propeller and divers were called in to free the entangled hose.
An incident like this is not only a risk to the safety of the vessel but also to the installation as the vessel may lose the ability to manoeuvre effectively.
Masters and offshore installation managers are reminded of the guidance in Appendix K, Section 8 of the NWEA Guidelines (below) as to the correct number of flotation collars that should be fitted for each bulk hose type.
Flotation collars can be of the ‘lace-on-jacket-type’ or made from polystyrene moulded section. The latter are banded onto the hose and all collars have a highly visible colour.
Lace-on collars should be secured using Manila rope rather than man-made fibre to avoid slippage. The rope should be secured to the hose, threaded through the jacket eyelets and finally tied off on the hose at the other end.
Self floating hoses do not require to be fitted with floatation collars.
Masters are advised to raise the issue of insufficient flotation collars with the installation before starting bulk hose cargo operations.
If there are insufficient flotation collars, carry out a risk assessment to ascertain if it
is safe to commence hose operations.
The full safety alert can be downloaded here.