摘要
AMCA 208規範為美國空氣流動和控制協會（Air Movement and Control Association，AMCA）所訂定新的風機能源指標FEI（Fan Energy Index），FEI是風機革命性能源指標，有別於先前AMCA 205所述之FEG（Fan efficiency grade），與歐盟及ISO所採用之FMEG（Fan motor efficiency grade）也有所不同，FEG與FMEG皆是著重於風機的最佳效率點，但實務上風機的運用，通常其操作點並不是最佳效率點，換言之，風機是在其效率較低的條件下使用，無法達到設計者所要達到省能目的，FEI即是試圖解決這樣的盲點，風機選用是根基於相同操作點之風量與風壓來決定，只有滿足這些特定條件，且有較佳能效的風機才會被選用，這有助於更好地選擇風機類型和尺寸，節能也才會被真正實踐，FEI與FEG相較，FEI可讓消費者更清楚明瞭所使用之風機的能效等級，對於風機的設計者也將更有彈性，法規的執行更為簡單可行，也更能達到省能的目的。FEI目前仍由AMCA和美國能源部（DOE）共同推動和制訂成為聯邦法規的階段，儘管如此，美國一些州已考慮採用此一指標，AMCA的最終目標是提交給ISO，並建議將FEI訂定為國際標準。
並列摘要
The AMCA 208 standard is a new fan energy index (FEI) set by the Air Movement and Control Association (AMCA). FEI is a revolutionary new fan-efficiency metric. It is different from the FEG (Fan efficiency grade) as defined in AMCA 205, and is also different from the FMEG (Fan motor efficiency grade) adopted by the European Union and ISO. Both FEG and FMEG are based on the fan's peak total efficiency, but in real application, the fan's operating efficiency should not just evaluated on the peak total efficiency point. In other words, the fan is used below the peak total efficiency, and cannot achieve its design goal of energy-saving. To overcome such blind spots, FEI emphasizes that fan selections should be based on real operating points. Only those fans meet certain operating conditions with higher efficiency will be selected. The benefits of FEI include clarity for consumers, flexible application for designers, simpler and more feasible for regulatory officials, and more energy-savings. Currently, FEI is in the stage of being promoted and set as a regulatory code by AMCA and the U.S. Department of Energy (DOE) and not yet being completed. Despite the current status, this metric is considered to be adopted by some States in the US as the appliance energy efficiency code in the preliminary stage. The AMCA's goal is submit FEI to ISO and set as the international fan efficiency standard.