空氣清淨機測試方法評估

Evaluation of Test Method of Indoor Air Cleaners

侯冠廷(Kuan-Ting Hou)

指導教授 ： 陳志傑

國立臺灣大學/公共衛生學院/職業醫學與工業衛生研究所/碩士(2006年)

https://doi.org/10.6342/NTU.2006.01028

摘要

現在歐美廣泛使用的空氣清淨機效能測試方法：ANSI/AHAM AC-1-2006，為美國國家標準協會/美國家電製造商協會（ANSI/AHAM）於2006年所公佈並以CADR（Clean Air Delivery Rate，CADR）值做為空氣清淨機效能的評估指標。在本研究中，將對AC-1-2006現行方法中測試條件的合理性進行評估，考量不同的微粒產生條件以及不同大小及洩漏量的測試空間、微粒量測儀器其與空氣清淨機擺設之相對位置對於室內空氣清淨機的評估指標CADR值的影響。實驗結果將有助於建立一個更完備的空氣清淨機效能評估測試方法，並增加其評估結果的可信度，提供給消費者和製造商參考。

本實驗結果顯示，微粒在室內空間的衰減率與其粒徑大小有關，在0.3μm左右的微粒有最低的自然衰減率。在標準測試空間的環境下，改變微粒量測儀器及待測空氣清淨機之相對位置對衰減率量測並無影響。過高的微粒起始濃度會因膠結作用而低估CADR值，當起始濃度＜105 #/cm3時膠結作用趨於不顯著。以小型測試空間是可行的，但需在系統洩漏造成影響前進行CADR計算。測試空間其洩漏量愈大時空間內微粒濃度愈早與外界達到平衡因而使得微粒的衰減曲線提早產生偏斜，若涵蓋到計算時間內會造成微粒衰減率的低估。所測試之空氣清淨機，當提升操作風量時CADR值增加，能量的消耗亦隨之增多。若考量單位能量消耗可得之CADR值則需考慮空氣清淨機之風扇設計。

關鍵字

空氣清淨機 ； 室內空氣品質 ； CADR

並列摘要

Indoor air cleaners are commonly used as an adjunct to source control and ventilation. In ANSI/AHAM AC-1-2006 (Method for Measuring Performance of Portable Household Electric Room Air Cleaners), Clean Air Delivery Rate (CADR) is a measure of the appliance’s ability to reduce aerosol particles in the 0.10 to 11 μm size range. In the present study, the effects of test chamber size, aerosol size (distribution), aerosol number concentration, position and flow rate of aerosol spectrometer, and leak rate of the test chamber on the CADR measurements were investigated. Two types (ESP and filter) of commercially available indoor air cleaners were tested in a standard certification chamber, and a chamber only 1/8 of the volume. Polydisperse aerosol particles were generated using a constant output aerosol generator and an ultrasonic atomizer. Aerosol outputs from both generators were then neutralized by using a radioactive source (Kr-85) to neutralize the aerosol particle to the Boltzmann charge equilibrium. The main aerosol size-spectrometers were a Scanning Mobility Particle Sizer and an Aerodynamic Particle. The background decay rates were measured by using real time aerosol instruments and a Mini Infra-Red Analyzer (MIRAN) was used when SF6 was the test agent.

The results showed that CADR value is a function of aerosol size. The ESP- and filter-type air cleaners had significantly different characteristic CADR curves. In general, ESP air cleaner performed better in aerosol collection, air resistance, and power usage. The relative location and orientation of the air cleaner and aerosol spectrometer in the test chamber had almost no effect on the CADR measurements. The measured CADR values decreased with increasing aerosol number concentration apparently due to coagulation effect during the natural decay measurement. The coagulation effect became less significant if aerosol number concentration was lower than 1.0×105 #/cm3. Use of smaller test chamber is possible. However, only the data collected before infiltrated aerosols became significant should be used for calculating the CADR value. Room air cleaners with multi-level performance fan settings normally delivered higher CADR when operated under higher air cleaning mode setting, but not necessary the CADR/watt value, probably due to the difference in fan performance curve.

並列關鍵字

Air cleaners ； Indoor air quality ； CADR

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