A unified grading standard for heavy pollution warnings will be adopted in China's very polluted Beijing-Tianjin-Hebei region by the end of October, which may effectively tackle the region's deteriorating air pollution.

"The Beijing-Tianjin-Heibei region has suffered three long-term and large-scale bouts of air pollution since last winter. Though the level of air pollution may be similar to that in many cities, [the different warning systems of Beijing, Tianjin and Hebei] have hindered the joint effort to curb smog, as well as adversely affected regional cooperation on pollution management," said an official from the Ministry of Environmental Protection to the Beijing Times.

According to the standard released in the beginning of 2016, the pollution warning system for six major cities in the Beijing-Tianjin-Hebei region contains four tiers and is color-coded, with red representing the most severe air pollution, followed by orange, yellow and blue. A red alert is issued if the predicted Air Quality Index (AQI) reaches 500 and is projected to last for over a day, or if the predicted AQI is higher than 200 for three consecutive days.

By the end of October, more cities in the region will adopt this warning system, as well as several cities in Shandong and Henan provinces.

As one of the most polluted areas in China, the Beijing-Tianjin-Hebei region is home to China's largest steel and iron manufacturers as well as some of the most polluted cities in the world.