See-through mask aids talk between the deaf

Erin Chan

Around 65,000 masks that make lip reading easy for deaf and hearing-impaired people are now being distributed to 14 non-governmental organizations.

The masks - disposable and being handed out without charge - include a see-through film to display lip movements.

There are currently more than over 150,000 people who have hearing problems, and the Caring For Children Foundation says that over 90 percent of them communicate with lip reading or hearing aids.

The masks were developed in a four-month joint effort between the foundation and SPRO Medical Products at Hong Kong Science Park.

The project took shape after a failure to source such a product from overseas-based makers.

Lok Chan Man-lok, general manager of the Caring For Children Foundation, said the need for such masks became apparent as the foundation distributed ordinary masks to NGOs.

She said the foundation hoped the masks would also become available to carers of the deaf and hard-of-hearing, children with special education needs, speech therapists and some retailers.

The head of research and development at SPRO, Chan Miu-shan, said the mainland-made masks were similar to ones available in South Korea but have a smaller transparent section.

"Our concern was that the bigger the transparent film the lower the filtration efficiency," Chan said.

The transparent film is also coated with a layer of anti-fogging material so vapor from exhaled breath does not obscure lip movements.

Tang Siu-chung, a hard-of-hearing primary school teacher who has students with the same problem, said communication had been difficult.

"The sign language for words such as "coke" or "bank account" is the same," Tang explained, "but when you can't see the lip movement of somebody [as they are wearing a regular mask] it affects the delivery of words."

He recalled an occasion when he was scolded by passers-by after he removed his mask to show his lip movements to hard-of-hearing friends.

On a related subject, researchers at the University of Science and Technology said last week they had developed an ultra-thin polymer nanofilm - an advanced material that can be used for transparent masks.

The material is only 20 nanometers thick - less than 1,000th the thickness of a strand of hair - and extremely transparent, gas-permeable and waterproof, making it suitable for use in wearable devices.