Tough restrictions on vehicle access to central Beijing are included in measures to be implemented from tomorrow to combat air pollution, an environmental official said yesterday. Only liquid petroleum gas powered vehicles, or those certified as environmentally friendly, will be allowed on roads into the city centre every day. Other vehicles will be subject to an alternate-day system based on the last digit of licence plate numbers. Six air quality monitoring stations will be installed in city areas and police will check vehicle gas emission. Beijing Environmental Protection Bureau director Zhao Yijin said the measures would last until March. The next five months were the worst for pollution in Beijing, Xinhua quoted Mr Zhao as saying. The new measures also include closing a furnace at the Beijing Capital Steel Plant, closing an alloy manufacturer and a cement factory and suspending production at a coking plant. Beijing Capital Steel is required to submit a plan to cut steel production by two million tonnes by 2002. All heaters and industrial boilers in Beijing must use coal with low sulphur content. Suburban residents have been told to use clean fuel and avoid coal cinder. Winter in Beijing is notorious for poor air quality. Sandstorms that originate in Mongolian deserts often engulf the capital for days, disrupting air and land traffic. Mr Zhao said the goal was to 'significantly reduce' air pollution this winter and next spring. 'We hope that the air quality for 40 per cent of the time in this period will reach Grade Two [Good] of our air quality standards,' he said.