2. The concentration of flue gas and other pollutants must meet the national Emission Standard for Air Pollutants of Boilers (GWPB3- 1999) and Emission Standard for Smoke and Dust of Industrial Kilns (GB9078- 1996).
3. Under special circumstances such as raw furnace ignition and furnace cleaning, the smoke blackness shall not exceed Lingemann III, and the discharge time shall not exceed 10 minute.