IT'S late on a Friday afternoon - just enough time to guzzle a can of San Miguel before the number 20 bus heads to Central from the Shau Kei Wan terminus. This is your peak-hour driver. On two occasions this same man has been recorded getting into the driver's seat to take the number 20 to Central after drinking beer. The first time he did it within full view of a bus inspector. On the second occasion he was seen returning 11/2 hours later with a bus load of passengers. He is not the only one. From a vantage point overlooking the terminus, a number of China Motor Bus (CMB) drivers were noted breaking company rules - but not the law - by drinking and driving. For regular commuters there it is not an unusual sight. Another CMB driver began drinking a large bottle of Heineken at 6.20pm. At 7.05pm he boarded a bus, beer bottle still in hand, and moved it to another part of the terminus. Fifteen minutes later he got into the driver's seat of the same number 720 bus and drove it away, his indicator signalling he was going in the opposite direction to the left hand turn he made. While the lights were off and this bus was not carrying passengers, the news that CMB bus drivers are drinking and driving was met with alarm by legislators, social workers and CMB officials who claimed their drivers did not drink and drive. According to studies by the National Health and Medical Research Council of Australia, after consuming anything more than half a pint of regular beer - one unit of alcohol - a person may begin to show signs of intoxication. When a person consumes four units of alcohol in one day, they will begin to show signs of ''dysfunction''. When told of the incidences, convenor of the Legco Transport Panel, Liberal party legislator Miriam Lau Kin-yee, stated: ''This kind of behaviour cannot be tolerated. ''I would expect the company to take concrete action. This is a very grave matter.'' She went on to say that if there was sufficient evidence that CMB bus drivers were drinking and driving, then the panel would certainly bring it to the attention of the Government. ''It is the responsibility of the panel to bring it to the attention of the administration,'' she said. A return visit to the Shau Kei Wan terminus to talk to bus drivers, an estimated 200 of whom face the axe once route cuts come into effect on September 1, found them unhappy with their work and disgruntled with their employer. But all denied there was any drinking on the job. At 4.30pm, half a dozen CMB drivers in sweaty blue T-shirts and shorts were gathered around a wooden table outside the station master's booth, eating snacks and drinking bottles of imported beer. As their conversation and laughter grew louder, passers-by and waiting passengers turned to stare. But, the drivers said, it had been a long, hot eight-hour shift at the wheel. Now it was time to relax; to eat, drink and chat with fellow drivers after a hard day's work. By early evening, one or two drivers appeared tipsy. Would they drive a bus again that evening? ''Certainly not!'' they chorused, angered by the allegation. ''We do not drive after we have been drinking beer,'' one driver said. A night shift driver opened his flask. ''As you can see,'' he said, ''this is filled with hot tea.'' Other drivers said the same. ''[Drunk driving] is strictly prohibited by the company. The practice is far too risky. What would happen if someone accidentally bumped into our bus? Even if it wasn't our fault, if the police smelt alcohol on our breath, we'd be arrested,'' said a 45-year-old driver. The others agreed. Many were in their 30s and 40s and had been driving buses for the last 10 years. When asked whether they knew of cases in which a bus driver was dismissed because of drunk driving, one said:''We have not heard of anyone being fired for that reason. But if someone did get caught, he would surely be out of a job now.'' They did however admit to being under stress. ''We are under a lot pressure. . . pressure from the company which expects us to be polite and courteous to all passengers, even rude ones, and from driving in the congested traffic,'' a young driver said. ''We don't earn easy money. So at the end of the day, we enjoy having a beer. Not all of us are into soft drinks.'' All drivers work in shifts but to earn more, some work for up to 15 hours with only two brief breaks. According to one pay slip, a bus driver had worked 15 hours a day for two weeks and had accumulated $7,000. ''You can make more money by working long hours but it is a very tough way to make a living,'' the young driver said. According to CMB spokesman Ng King-chung, the company does not allow drinking on the job. He said he did not know of any report or complaint that employees were drinking and driving. ''Nobody will take this risk. But if evidence was provided, we would take action. We would conduct an investigation and the driver would be taken off driving duty. ''It may lead to him being laid off or transferred to another position because this is very serious. As a bus company we cannot let this sort of thing happen.'' CMB is already battling dissatisfaction over its service. From September 1, it will lose 26 of its 890-odd routes to Citybus. The reduction was part of a franchise package passed by the Executive Council and accepted by CMB last July, forcing it to fulfil broken promises of better management and service. The 26 routes lost have been the subject of most complaints from the public. The company will also lose its profit-control scheme, which guaranteed a 15 per cent profit return for the company. CMB has operated bus services on Hongkong Island for nearly 60 years. According to Miriam Lau, the attitude of CMB drivers and the whole company ''have been at the root of complaints for a long time''. The problem with CMB is its management, she added. ''It is a long-standing problem and it is about time the company pulled up its socks. Management could work in such a way as to boost the morale of the drivers, to make them dedicated to their work and proud to be driving for CMB. ''The company has another two years. All these matters will be taken into consideration,'' she said. While CMB drivers who drink are breaking company regulations, they are not breaking Hongkong law. The law makes no distinction between private and public drivers and it would be a matter of internal discipline, according to the Transport Department. Only one law covers drink driving in the Road Traffic Ordinance - ''Driving a motor vehicle under the influence of drink or drugs''. But there is no set limit for police or medical staff to use as a guide and a driver is under no obligation to submit to a blood-alcohol or breathalyser test, which are conducted at hospitals. About one year ago a working group on drink-driving was set up to examine the adequacy of present legislation. The Transport Department's senior engineer in the Road Safety and Standards Division, Ching Kam-cheong, admitted there was ''room for improvement''. One of the problems facing the working group is a ''vicious circle'' dilemma, according to Mr Ching. ''If you don't have a good law, you can't get the statistics, without the statistics you can't prove that the law is bad.'' And police records show drink-driving is not a problem in Hongkong. In 1992, the police recorded 18 cases of drink or drug abuse under section 39 of the Road Traffic Ordinance. In the first quarter of this year, there were eight. The story of the bus drivers, the can of San Miguel and the bottle of Heineken was recounted to Enid Craig of the Community Drug Advisory Council. She described it as ''appalling''. ''I would think there should be strict monitoring of what they drink if they are going to be in charge of a vehicle with any number of innocent passengers on board. ''I don't think it is recommended that anybody in charge of public transport should drink.''