THE SOUND of laughter punctuated proceedings as the Dibden Bay public inquiry continued to debate the noise impact from the proposed container port on surrounding villages.

But there was a good excuse for a moment of levity at the normally solemn hearing which is taking place at Southampton's Eastern Docks. The inquiry is celebrating its centenary.

"Happy Birthday everyone. This is our 100th day!" said deputy inspector Andrew Phillipson as he took his seat. Acoustics consultant Robert Davis caused hilarity when he launched into his speech without switching on his mike. " A sound expert who can't work the sound system!" he joked. And further amusement was triggered when siren blasts from passing shipping repeatedly drowned out Mr Davis's evidence on the "annoyance factor" of noise and vibration.

But Mr Davis, 34-years an acoustics expert and researcher for Southampton University, was determined to make himself heard on behalf of New Forest District Council.

"Even if mitigating measures were adopted, I consider that the construction and operation of the proposed Dibden Terminal will have a significant adverse impact on the noise climate of the surrounding area," he said.

Mr Davis summed up the possible future for the eardrums of Waterside residents:

A nine-year construction period including the building of a quay wall nearly 2km long, which would need up to 900 massive piles driven into the sea bed by a 45-tonne hammer. Each pile would need up to an hour of hammering, one bang every second.

Once the six-berth container port was operational it would mean about 7,000 extra vehicle movements a day on surrounding roads.

Trains on the Fawley branch line would increase from seven per day to 48 - including 28 at night.

And the terminal itself would be operational 24/7, with noise from ships' engines and generators, fans, container-shifting and vehicle movements a constant factor in the lives of people living nearby.

"Quay wall piling within 1,200 metres will be perceived as repeated rapid displacements of the building structure. Vibration will cause rattling of radiators, doors and glassware," said Mr Davis.

"A regular pattern of noise, where you sit anticipating the next blow, can be much more annoying than a sudden unexpected noise."

Mr Davis questioned the validity of methods used by sound experts for Associated British Ports - who are behind the Dibden Bay scheme.

"Their measurements are not reliable. Baseline surveys to assess present background noise levels were only taken over 24 hours, always on a weekday. That is not enough time to judge impact," he said.

At the inquiry on Tuesday afternoon Totton councillor Edith Randall also questioned the value of machinery to assess noise.

"Your highly sophisticated instruments don't have the same perception of noise and vibration as the human ear. They can't say 'I'm fed up with this!'" she said.