HC Deb 16 January 1978 vol 942 cc15-6W
Mr. Skeet

asked the Secretary of State for Energy whether marine life is causing a serious problem for offshore oil and natural gas platforms; what degree of risk is involved; what steps are being taken to cope with the growth of marine life; and what is the likely impact on the number of divers required.

Mr. Benn

Marine life, in the form that attaches itself to offshore oil and gas platforms, is a problem in varying degrees for the following reasons:

(1) Marine life that grows on offshore installations increases the fluid loading on the structure and therefore have to be kept within given limits, which vary according to the design parameters, to prevent possible over stressing of the structure.

(2) It hampers the work of inspection, repair, and maintenance of offshore platforms.

(3) It is thought possible by some that some types of marine growth may affect the corrosion of steel structures.

The degree of risk regarding overloading of the structure is negligible provided the quantity of growth is kept within design parameters. However, risk is involved in its removal. It is the general practice at this time to use divers, using hand or mechanical tools, to remove marine growth. The degree of risk for this latter case is the normal risk of any diving operation carried out in United Kingdom waters for offshore structures.

The steps that are taken at the present to control the quantity of marine growth that accumulates on a structure is to remove it as described above. However, the Department is supporting a number of research projects which are carrying out investigations into possible new methods of inhibiting marine growth and methods for its removal by remote-controlled vehicles, submersibles, and other methods which should reduce the amount of time that divers have to spend in the water. Advice is obtained from various working parties whose membership include representatives from industry, consultants, Government Departments and universities.

The number of divers involved in such work will depend upon the results of the above research but if the results do not prove to be useful it is anticipated that the number of divers involved will increase due to the increase in the number of offshore installations and possible increase in the amount of repair and maintenance that will almost certainly be necessary as the installations get older.