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Tangshan Tonghai Air-Cleaning Technology Co., LTD., founded in 2017, focuses on controlled environment technology and equipment (including ventilation control and ventilation safety). At present, it has formed a research and development center, sales and marketing headquarter in Beijing, a factory in Tangshan, and an office for international business in Hainan Free Trade Port. We dedicate in the fields of nuclear industry ventilation equipment, life science, and physical and chemical laboratories.The company has been making efforts on the pain points of the users, and has achieved significant breakthroughs in air valve controls, air tightness, disinfection, leak detection and other technologies with a number of invention patents.The ventilation safety products, independently developed by the company, include air tight isolation valve, regulating valve, bag-in and bag-out HEPA filtration device (BIBO), terminal HEPA filtration device, Y type air vent HEPA filtration device, etc., have o...