5.氣瓶獨(dú)立檢驗(yàn)機(jī)構(gòu)(Independent Inspection Agency,IIA)鋼印標(biāo)記。截止到目前,美國(guó)運(yùn)輸部批準(zhǔn)的獨(dú)立檢驗(yàn)機(jī)構(gòu)在美國(guó)有12家,每個(gè)獨(dú)立檢驗(yàn)機(jī)構(gòu)都有自己的監(jiān)檢鋼印和ID號(hào)碼。這12家獨(dú)立檢驗(yàn)機(jī)構(gòu)分別是; Arrowhead Industrial Services,Inc; Authorized Testing,Inc; T. H. Cochrance Laboratories; Bureau Veritas North America,Inc: Professional Services,Inc,; HSB Global standaeds; Stork Herron Testing Laboratories,Inc.; Steigerwalt Associates; M.R. Wright & Associates Co.,Ltd; Cylinder Services,Inc.; G & C Kinner,Inc.; Global Approvals, LLC。