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“Yao’an” is a high-tech enterprise specializing in industrial gas alarms,environmental monitoring analyzers,and integrated fresh air system for smart home. Currently, "Yao’an Holding Group" has many branches.It started the business of gas alarms in 2007, and has been engaged in the industry for more than a decade. It is located at China (Shandong) Pilot Free Trade Zone,Jinan Area,HanYu Gold Valley, the central business district possessing an office area of more than 3,000 square meters. It has more than 30 patent certifications,more than 20 metrology certifications, more than 40 explosion-proof certifications,international quality management system ISO9001 certification, environmental management system ISO14001 certification, occupational health and safety management system OHSAS18001 certification, fire protection product certification and other relevant certifications over 30.