| A scene from the film Shark Tale
London, Oct. 17: The latest crop of noisy children's films don't just keep youngsters quiet for an hour or so. They can permanently damage a child's hearing, with some so loud that they are the equivalent of a jet plane taking off, according to new research.
The findings confirm what many parents may long have thought: films are getting louder.
Armed with sound meters, a team of American paediatricians, tested decibel levels of 23 recent releases.
They found that some sequences were as loud as standing near a jet taking off, and many, breach UK guidelines designed to protect employees in the workplace.
Dr Loren Yamamoto, who oversaw the US study, said: 'When we think of loud movies that could harm our hearing we typically think of Terminator or something along those lines. Most people never suspect children's films are as loud or potentially damaging. Hopefully, our findings will change this perception.'
Some films showed peaks of 130 decibels during car chase scenes, gun fights and explosions ' the equivalent of standing just 100 yards away from a jet during take-off.
Although the children's films did not have the same high aural peaks as adult action films, they were generally louder throughout, giving them the same average sound rating as action films.
Britain's Health and Safety Executive has set limits for how much sound people can be exposed to at work, with anything over 85 decibels considered potentially dangerous.
The increase in cinema sound volume can be blamed on two causes: the soundtracks are louder and cinemas, wanting to show off their 'surround sound' speaker systems, turn up the amplification.
Using a sound meter to measure the sound of the new animated film, Shark Tale, which features the voices of Robert de Niro, Will Smith and Renee Zellweger, found that it was regularly in the high 70 to low 80 decibel range, with a peak during a climactic fish fight scene of 85.8 decibels. Some of the film trailers and advertisements that preceded it also breached the 85 decibel safety level.
Much more of the film would have been considered damaging if measured against new European Union regulations which, in two years' time, will reduce the safety threshold to 80 decibels.
Angela King, a resident audiologist with the Royal National Institute for Deaf People (RNID), was not surprised by the findings. 'You rarely hear someone come out of a cinema complaining that they could not hear the quiet bits of the film,' she said.
'After a very loud film, you will get a buzzing or ringing in your ears. People then recover, the buzzing or dullness in hearing goes away, and they think they are fine ' but the damage has been done.'
King warned that each time the ear was assaulted by loud noise, cells were damaged or destroyed, eventually leading to a loss of hearing. Harm done in childhood would accumulate and show up later in life.