The difference between the role of exhaust fan exhaust fan and positive pressure fans is this: When the basement fire, there is a lot of smoke produced, exhaust fan fire, this time, sales exhaust fan, fire start with exhaust fan, the occurrence smoke fire area excluded. In addition, it can usually exhaust fan in a basement also for air. Positive pressure blower is pointing escape corridor air supply fan. It outdoor air pressure into the interior. When the building is on fire, it will produce a lot of smoke, carbon monoxide and other toxic gases and block the line of sight, through positive pressure blower air to escape the fire stairs, indoor smoke can not reach the stairs, to create conditions for people to escape. If the blower is located in the roof of high-rise buildings, sending through the pipeline to the stairwell or elevator shaft front room fan, exhaust fan, then known as positive pressure air supply, its role is to fire at the floor, stairwell or elevator to the front compartment blower, guarantor of safe evacuation. Exhaust fan in the smoke control system, the role of smoke control system, it is taken together, it is the only exhaust systems and smoke control system. Fire and smoke control system refers to when supply exhaust fan, the need to set the area smoke positive pressure air supply system to ensure the safety of personnel in the region. Usually smoke stairs, before room. Exhaust systems means provided in a certain area, when a fire, the fire will exhaust fan exhaust area of ??the system. Smoke system is pressurized to the regional air blower, exhaust system exhaust fan to exhaust fumes. The purpose is to ensure the safety of the fire and rescue region were. Sheng clean air conditioning (Figure), high-temperature exhaust fan, exhaust fan from the Texas Sheng provide clean air-conditioning Limited. Texas Air Conditioning Equipment Co., Ltd. Sheng-purification (www.dzhffj.com) located in Dezhou City, Shandong Province, Wuhan City acres of industrial park. Scraps and development in the wave of market economy, the current clean air conditioning Sheng Tong has a high profile in fan, ventilation equipment, and enjoys a good reputation. Sheng purification of air conditioning made the whole network business alliance certification, marking our service and management level has reached a new height. Sheng clean air-conditioning staff willing to work with all people of insight and common development, for a better future.