The young man on the jackhammer pounding out his headache-rending pavement percussion is an obvious example. If he doesn't wear his ear protection gear, he'll be deaf before he's 40. But there are other, less apparent jobs that are high-risk areas for occupational deafness. How about restaurant waiters, cooks or mahjong parlour workers? It may not be easy to draw a parallel between jackhammer, kitchen utensils and the clack of mahjong tiles on tabletops, but the noise from each of them can reach 90 decibels or more and cause permanent hearing loss, according to the Occupational Deafness Compensation Board. Abattoir workers who operate stun guns, chefs and waiters who work in or near noisy restaurant kitchens, and mahjong parlour workers are among 29 high-risk occupations identified by the occupational deafness compensation scheme in Hong Kong. Workers from the identified categories are eligible for compensation if they are diagnosed with hearing impairment of at least 40 decibels in each ear, and have been in the same job for a minimum of five years, depending on the nature of their work. An impairment of 40 decibels means a person cannot hear sounds that register below 40 decibels, which is considered the level of a normal speaking voice. Most of these 29 noisy occupations involve the obvious offenders - construction work, jobs involving power tools, factory machinery, or work near engines. Since the Occupational Deafness Compensation Board was set up - 10 years ago on June 1 - it has received 4,397 applications for compensation, of which about half - 2,191 - were successful. Compensation is only given to those with permanent hearing loss or impairment. Fifty-three per cent of the successful applicants (1,175) are less than 56 years old. Nearly 60 per cent of successful applications (1,279) come from workers who carried out rock grinding, chiselling, cutting or percussion work - areas mainly related to construction. Nearly 6 per cent, or 126 successful claimants, worked near combustion engines or pressurised fuel burners. These include restaurant staff. 'Imagine the loud noise created by several jumbo-size pressurised fuel burners together with the sharp metallic noises created by the utensils when tens of kitchen workers are preparing food in a restaurant kitchen at the same time,' said Lawrence Li Kwok-chang, chairman of the Occupational Deafness Compensation Board. 'The detriment to the ears is equally severe for abattoir workers who are exposed to the sharp noises of the electric stun gun, together with the squeals of hundreds of pigs everyday,' said Dr Li, an otorhinolaryngology (ear, nose and throat) specialist. He said noise pollution was enormous sound energy that could cause permanent injuries to nerves inside the ears if people were exposed to such an environment for long periods of time. The severity of impairment depended on the loudness of the pollution and the length of the time of exposure. Most injuries to the delicate inner-ear nerves are irreversible, but hearing aids may improve the hearing of people whose impairment is not too severe. According to the board, the noise pollution in a typical disco is 95 decibels for the disc jockey and 91 for waiters serving drinks. Mahjong parlour workers and slaughter-house employees suffer about 92 decibels at work. To put this in proportion, a high-powered electric drill runs at 100 decibels. Besides awarding compensation to victims of occupational deafness, the board has a statutory role in preventing deafness by helping workers and employers take preventive measures. Dr Li said that after 10 years of effort by the board, employers and workers from the construction and catering industries had become more aware of the health risks and were happy to follow the board's suggestions. He said more employers were changing to new and quieter machines and equipment, and offering staff job rotation to provide temporary relief from particularly loud areas. Workers were also more willing to put on their ear plugs, after being informed of the risks involved to their health. 'Ten years ago, many employers and workers snubbed our advice because this kind of work [without noise protection] environment had been fully accepted by the industries,' Dr Li said. 'But their attitude has completely changed now. We are constantly invited by construction companies to hold talks on noise management.' This new-found awareness is believed to be a key factor behind a sharp drop in new cases registered by the board in recent years. However, Dr Li said the migration of factories to the mainland was believed to be another contributor to reducing the number of occupational deafness cases. But problem areas continue to exist. 'Many people are not aware of the risks of noise pollution in work environments such as mahjong parlours and discotheques,' Dr Li said. The major obstacle for the service industry is that workers have to communicate with their clients, making it impractical for them to put on ear plugs in noisy clubs and bars. Dr Li said the board was now targeting mahjong parlours and loud nightclubs. These represent their own peculiar challenges. Of about 70 mahjong parlours across the territory, the board has so far only approached one with any success. 'It was not until very recently that we successfully visited a mahjong parlour,' said Lai Ka-tong, executive director of the board. 'It has taken us a long time to persuade them to allow our visit. 'The parlour owners keep telling us that their customers enjoy the loud noise when they reshuffle the 144 mahjong tiles and hit them heavily on the gambling table. 'The customers insist that they not place any soundproof padding on the table to lower the decibels. They say it would ruin the atmosphere.' The board faces similar barriers with discos, and has again only had a positive response from one so far. Mr Lai said waiters and waitresses who worked in discos thought it was impractical to wear ear plugs because they needed to communicate with customers. He said disc jockeys were another high-risk group due to the close proximity to loudspeakers. Since wearing ear plugs was impractical for those workers, the board recommends employers rotate their staff across different areas. 'Undoubtedly we cannot expect to change long-standing business practices and cultures overnight, as with the smoking ban,' Dr Li said. 'But the business owners have been made aware that their workers are among the high-risk categories for hearing loss. We have opened the door with at least one discotheque and one mahjong parlour allowing us to visit and explain the situation.' In 2003, the board was given the added task of overseeing statutory rehabilitation. The new role was aimed at helping workers remain in the same job or find another occupation. So far, about 500 victims of occupational deafness have received subsidies from the board to buy hearing aids. A retired construction worker who only identified himself as Mr Ho, was among the applicants who received $50,000 in compensation from the board in 1998. The 74-year-old, who worked in the construction industry for half a century until he retired in 1998, suffers from a permanent hearing impairment, and now depends on a hearing aid subsidised by the board. He said that he chose not to use ear plugs to avoid risking potentially fatal industrial accidents. 'Our employer gave us the ear plugs but most of us did not use them because it would be even more dangerous if I could not hear people shouting that there was danger,' Mr Ho said. 'So I preferred losing my hearing than losing my life. 'It was not until the late 1980s that occupational deafness became an issue to the construction industry. In the past, workers accepted the noise pollution as normal and no one was aware that it would create a health problem. 'Of course, it is very sad to lose your hearing ability. The problem brings a lot of inconvenience in life, such as some people being reluctant to talk to you.' Mr Ho is also a victim of pneumoconiosis caused by his work and is now on $3,000 a month in compensation from the Pneumoconiosis Compensation Fund Board. 'Life was so difficult in the old days,' he said. 'People who are illiterate like me had to accept the hardship and risks at work. I didn't think of my health at all. The only thing I cared about was making a living to raise my family.'