Beijing has issued its first orange smog alert ahead of winter today, forecasting heavy air pollution over the next four days. According to a notice posted on Weather.com – a website affiliated with China's National Meteorological Administration said,vehicles with National I and II emission standards and trucks transporting waste earth and construction debris will be banned from roads between 4th and 8th November. <br/><br/>Authorities in smog-blighted northern provinces such as Hebei, Henan, Shandong and Shanxi have urged their major industrial cities to slash steel output ahead of winter, to cut levels of hazardous airborne particles. China's Environment Minister Li Ganjie acknowledged last month that the government's efforts to meet air quality targets for the year face huge difficulties.