Three points to note the content of the calculation of fresh air room "public building energy efficiency design standards" GB50189-2005 design requirements for fresh air, make provision in clause 3.0.2, specifically, between 10-30m3 / (hop) between that there is fresh air 30m3 per person for the first hour. For indoor fresh air can be controlled by using the new air system operation, fresh air is mainly determined by means of GB / T18883-2002 referenced standards, the standard advice is to use the preparation department recommended standard "indoor public places Determination of fresh air" GB / T18204.18 wind chassis detection methods, but the use of GB / T18204.18 process need to pay attention to several aspects of the problem, in order to ensure the accuracy of the measurement results. First, the choice of tracer gas, we think the most appropriate selection of carbon dioxide, on the grounds that carbon dioxide is a substance involved in the body's metabolism in human exhaled gases, carbon dioxide accounted for 4% to 5%, and also in most countries The basic method used. The method of execution GB / T18204.18 choose carbon dioxide as indoor air freshness indicators to calculate the mass balance principle fresh air. Its basic theory is the concentration of carbon dioxide in the detection space control in 0.1%, to ensure that there are 30m3 of fresh air per person per hour, while the choice of carbon monoxide as a tracer gas is a better choice. Secondly, with regard to the calculation method of the fresh air, the standard GB / T18883 gives the average and regression equation method, using a box model, you can also use the differential method, the steady-state method for calculation. In practice, engineering test, in accordance with the standards, using non-linear regression method is the best choice, can accurately determine the value of the new wind system. Third Chongqing wind chassis, gas concentration detector used to detect the sensitivity should be sufficient wind chassis Tangshan, in general, should reach the precise 0.01mg / m3 requirements. Notes edit an air can not contain corrosive, viscous media can not contain. 2, medium temperature does not exceed 80 ℃, not lower than -10 ℃ 3, medium or hard-containing dust particles should not exceed 150mg / m34, be careful not to B-type fan used for firefighting purposes. 5, system design and fan selection should be made by professionals, and the system as much as possible to accurately estimate the negative force, otherwise it will lead to improper selection of the actual use of ineffective fan. 6, the pressure loss in the resistance component of the system is not a fixed value, should be used to calculate the drag coefficient for selection. 7, the cabinet should not be in full form of the fan (ie the fan inlet and outlet pipes are not connected) under long-term operation of the supply air box, because in such a strong fan performance state is unstable, and in this case , the motor fan is in overload standard configuration state, long-term use can lead to destruction of the motor, a short test machine is allowed Chongqing wind chassis _ Rich ventilation equipment (certified) _ Yangquan wind chassis provided by Dezhou Plumper ventilation plant . Dezhou Plumper ventilation plant (www.frtfsb.com) (www.frtfsb.com) is a leader in Dezhou, fans, ventilation equipment, over the years, the company implementing the scientific management, innovation and development, the principle of honesty and trustworthiness, the maximum limits to meet customer needs. Rich ventilation equipment in leadership with the staff warmly welcome all inquiries negotiations to create rich, ventilation a better future.