This had prompted his decision to fit a Wavestream bilge filter into his boat.

Upon returning to his boat, which had been left unattended at the Elizabeth Marina in St Helier, he discovered an oil leak from an engine pipe had left a thick layer of diesel oil floating in the bilge water. During the period of the leak, Stubbs estimated that the Wavestream filter had collected around a litre of diesel oil in the cylindrical cartridge filter that fits into the line between the bilge pump and the through hull outlet.

The actual cartridge uses a patented technology that attracts the oil content of the bilge water to bond to the filter element, allowing the cartridge to hold up to three times its own weight in oil.

A new filter from Stubbs' box of spares was installed, with a replacement spare purchased from Halyard. Since the Wavestream bilge water filter system was developed, boat operators are now able to comply with the stringent MARPOL environmental standards that require water pumped into seas to be less than 15ppm oil to water ratio. Rivers and waterways have equally stringent local controls and overseas marinas such as those in France are already fining boat owners who pollute the water with engine oil or diesel.

Initial trials over several years have been so successful that the Wavestream System 1000 filter has gained Lloyds type approval.

Used cartridges can be disposed of in the same designated bins used for other oily waste and are also approved for incineration. Harbour authorities and environmental agencies are themselves among Halyard's customers.

MJ Information No: 16831