Children at Morningside Kindergarten know when to turn down the volume thanks to a special safe sound indicator.

The device, which has been placed in 20 early childhood centres in Auckland as a pilot programme by the National Foundation for the Deaf, acts like a traffic light and flashes green, orange or red according to how loud the environment is.

The kindergarten has had the sound indicator for a month and head teacher Fiona McKenzie says it has become part of the furniture.

"We've been talking about it, all the kids know what it's for and have much more of an awareness about not getting up to the red light.

"It seems to be making a difference to the noise levels because of the increased awareness. It would be good to have it all the time as a permanent reminder."

She says the kindergarten has a great outdoor space that allows the kids to be loud outside and they work on using their "inside voices" inside the building.

"Rainy days are hard." .

After 25 years in early childhood education, Fiona says she has probably lost a little bit of her hearing and sometimes finds it hard to hear children with soft voices.

She says when the sound indicator goes up to orange, children and staff know to tone it down.

The programme aims to address noise-induced hearing loss in children and staff at the centres after a survey by the foundation of 65 centres, kindergartens and kohanga reo last year showed 20 percent of children had been affected by a high level of noise and reacted by doing things from putting their hands over their ears to being so distressed they cried.

More than a third of teachers reported buzzing or ringing in their ears from time to time and hearing loss which they believed could be a result of years working in a noisy environment.

Foundation chief executive Louise Carroll says the project is urgently needed to address the incidence of hearing damage in children and educators through repetitive exposure to excessive noise.

"We hope to have safe sound indicators in every early childhood centre in New Zealand within three years," she says.

- © Fairfax NZ News