Efficient test method for evaluating gas removal performance of room air cleaners using FTIR measurement and CADR calculation

We have developed a new test method for differentiating the gas-removal performance of indoor air cleaners by using Fourier-transfer infrared measurements and a clean-air-delivery-rate (CADR) calculation method in a closed test chamber (4 m3). Eighteen air cleaners were evaluated using both the new method and the current Korean and Japanese test methods, using ammonia, acetic acid, acetaldehyde, and toluene as test gases. The Association of Home Appliance Manufacturers’ statistical method for calculating regression line slopes of test chamber gas concentrations during air cleaner operation was used. The standard deviations of CADRs for ammonia, acetic acid, and toluene, gases that were easily removed by the air cleaners in the test chamber, were 3.2, 751.3, and 13.4 times higher, respectively, than the gas-removal efficiencies determined using the current arithmetic calculation method, which uses the ratio of concentrations after 0 and 30 min of air cleaner operation. The new test method clearly differentiated the gas-removal performances of various air cleaners, especially for gases that are quickly removed by indoor air cleaners. Also, the single-pass removal efficiency of the air cleaners was obtained with a simple calculation: CADR/flow rate/0.83.