"We recognise government's concerns about large, fast powered craft and personal watercraft, " said Howard Pridding, executive director of the BMF, "but for sailing craft, dinghies, narrowboats and smaller craft in general, unnecessary regulation will only damage recreation and tourism for no real public benefit."

"Our ports and shipping lanes are busy places where one wrong move can put lives in danger, " said shipping minister David Jamieson.

"Mariners, like drivers, need to have a clear head and I hope these new limits will make mariners think and not drink. I believe that by introducing these limits we will make our seas safer for everyone who uses them."

The regulations stem from the Marchioness disaster in 1989, where the dredger Bowbelle collided with the Marchioness Thames disco boat, capsizing her with the loss of 51 people.

The announcement of the limits for professional mariners means the government is fulfilling its pledge to implement Lord Justice Clarke's recommendation to introduce alcohol limits and tests for mariners, made his recommendation in his Thames Safety Inquiry and endorsed it in his report into the Marchioness Disaster.

Officials have been given powers to detain vessels pending the arrival of the police if they have reason to suspect that a drink driving offence is being committed. It is the police who will conduct the tests.

"The government is aware of the concerns of industry and users and we look forward to discussing this further during the consultation period, " Pridding told BB , highlighting widespread concern in the marine industry that increased regulation should not prevent the majority of people safely enjoying time out on the water.

"Nor should it have a negative effect on the water based tourism industry, Pridding told Boating Business.